Papers by Michelle Williams
Environmental Health Perspectives, 2017
BACKGROUND: Personal care products (PCPs) are exposure sources to phthalates and parabens; howeve... more BACKGROUND: Personal care products (PCPs) are exposure sources to phthalates and parabens; however, their contribution to men's exposure is understudied. OBJECTIVES: We examined the association between PCP use and urinary concentrations of phthalate metabolites and parabens in men. METHODS: In a prospective cohort, at multiple study visits, men self-reported their use of 14 PCPs and provided a urine sample (2004-2015, Boston, MA). We measured urinary concentrations of 9 phthalate metabolites and methylparaben, propylparaben, and butylparaben. We estimated the covariate-adjusted percent change in urinary concentrations associated with PCP use using linear mixed and Tobit mixed regressions. We also estimated weights for each PCP in a weighted binary score regression and modeled the resulting composite weighted PCP use. RESULTS: Four hundred men contributed 1,037 urine samples (mean of 3/man). The largest percent increase in monoethyl phthalate (MEP) was associated with use of cologne/perfume (83%, p-value <0:01) and deodorant (74%, p-value <0:01). In contrast, the largest percent increase for parabens was associated with the use of suntan/sunblock lotion (66-156%) and hand/body lotion (79-147%). Increases in MEP and parabens were generally greater with PCP use within 6 h of urine collection. A subset of 10 PCPs that were used within 6 h of urine collection contributed to at least 70% of the weighted score and predicted a 254-1,333% increase in MEP and parabens concentrations. Associations between PCP use and concentrations of the other phthalate metabolites were not statistically significant. CONCLUSIONS: We identified 10 PCPs of relevance and demonstrated that their use within 6 h of urine collection strongly predicted MEP and paraben urinary concentrations.
Journal of affective disorders, Jan 27, 2016
We sought to evaluate the prevalence and correlates of major depressive disorder (MDD) and suicid... more We sought to evaluate the prevalence and correlates of major depressive disorder (MDD) and suicidal behavior among urban dwelling Ethiopian adults. This was a cross-sectional study of 1097 outpatient adults (≥18 years of age) in a major hospital in Addis Ababa, Ethiopia. Sociodemographic and lifestyle characteristics were collected via structured interviews. MDD and suicidal behavior were assessed using the Composite International Diagnostic Interview (CIDI) among all study participants. Multivariable logistic regression models were fitted to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Prevalence estimates for lifetime and 12-month MDD were 18.0% and 6.7%, respectively. The prevalence of suicidal behavior during the previous year (i.e., suicidal ideation, plan or attempt) was 15.2% with approximately 4% having reported attempts. Overall, women were more likely to report suicidal behavior (17.8%) than men (11.3%). MDD odds were 1.53-fold higher among women as com...
Paediatric and perinatal epidemiology, 2016
Academics have a public duty to use their research to promote improvements in patient care and he... more Academics have a public duty to use their research to promote improvements in patient care and health. Here, we argue that there is an imperative to translate recent compelling evidence demonstrating the importance of the periconceptional period in determining the health of future generations, into improvements in pregnancy-related care and perinatal health. Taking this action has the potential to interrupt cycles of deprivation and to reduce inequalities in health. These are among the biggest challenges in health care today. It has been known for three decades that maternal exposures influence fetal growth and development by programming of the health of the newborn. 1 These changes persist into later life, and also affect health in the next generation, one example being the ongoing effects of undernutrition in those born or conceived during the Dutch Hunger Winter. It has become increasingly apparent that maternal characteristics not only affect fetal growth but also gametogenesis and embryonic development with lasting impact on health at birth and during childhood. 2,3 Periconceptional paternal influences on sexspecific fetal growth and long-term health of the offspring are also beginning to be seen. 4 The periconceptional period is therefore one of the most critical periods in the life course, initiating epigenetic programming determining perinatal health and wellbeing for generations to come. Perinatal health outcomes differ widely between countries, but even within high-income countries large differences in perinatal health outcomes exist. Perinatal mortality-as tip of the iceberg of perinatal morbidity-is an indicator of perinatal health. In cities like Rotterdam in the Netherlands, perinatal mortality
Journal of Sleep Disorders : Treatment and Care, 2015
Background-The Berlin and Epworth Sleepiness Scale (ESS) are simple, validated, and widely used q... more Background-The Berlin and Epworth Sleepiness Scale (ESS) are simple, validated, and widely used questionnaires designed to assess symptoms of obstructive sleep apnea syndrome (OSAS) a common but often unrecognized cause of morbidity and mortality. Methods-A cross-sectional study was conducted among 2,639 college students to examine the extent to which symptoms of OSAS are associated with the odds of common mental disorders (CMDs). The General Health Questionnaire (GHQ-12) was used to evaluate the presence of CMDs while the Berlin and ESS were used to assess high-risk for obstructive sleep apnea (OSA) and excessive daytime sleepiness, respectively. Logistic regression procedures were used to derive odds ratios (OR) and 95% confidence intervals (CI) assessing the independent and joint associations of high-risk for OSA and excessive daytime sleepiness with odds of CMDs. Results-Approximately 19% of students had high-risk for OSA while 26.4% had excessive daytime sleepiness. Compared to students without high-risk for OSA and without excessive daytime sleepiness (referent group), students with excessive daytime sleepiness only (OR=2.01; 95%CI: 1.60-2.52) had increased odds of CMDs. The odds of CMDs for students with high-risk OSA only was 1.26 (OR=1.26; 95%CI 0.94-1.68). Students with both high-risk for OSA and excessive daytime sleepiness, compared to the referent group, had the highest odds of CMDs (OR=2.45; 95%CI: 1.69-3.56). Conclusion-Our findings indicate that symptoms of OSAS are associated with increased risk of CMDs. These findings emphasize the comorbidity of sleep disorders and CMDs and suggest that there may be benefits to investing in educational programs that extend the knowledge of sleep disorders in young adults.
International Journal of Hypertension, 2011
Objectives. To examine the extent to which measures of adiposity can be used to predict selected ... more Objectives. To examine the extent to which measures of adiposity can be used to predict selected components of metabolic syndrome (MetS) and elevated C-reactive protein (CRP).Methods. A total of 1,518 Peruvian adults were included in this study. Waist circumference (WC), body mass index (BMI), waist-hip ratio (WHR), waist-height ratio (WHtR), and visceral adiposity index (VAI) were examined. The prevalence of each MetS component was determined according to tertiles of each anthropometric measure. ROC curves were used to evaluate the extent to which measures of adiposity can predict cardiovascular risk.Results. All measures of adiposity had the strongest correlation with triglyceride concentrations (TG). For both genders, as adiposity increased, the prevalence of Mets components increased. Compared to individuals with low-BMI and low-WC, men and women with high-BMI and high- WC had higher odds of elevated fasting glucose, blood pressure, TG, and reduced HDL, while only men in this ca...
Archives of Women's Mental Health, 2015
Purpose-The objective of this review is to summarize the literature (and to the extent possible, ... more Purpose-The objective of this review is to summarize the literature (and to the extent possible, report the magnitude and direction of the association) concerning history of CSA and depression or depressive symptoms among pregnant and postpartum women. Methods-Publications were identified through literature searches of seven databases (PubMed, EMBASE, PyscINFO, CINAHL, Web of Science, BIOSIS, and Science Direct) using keywords including "child abuse," "depression," "pregnancy," "prenatal," "pregnancy," and "postpartum". Results-The literature search yielded seven eligible studies on the prenatal period and another seven studies on the postpartum period. All, but one prenatal study observed statistically significant positive associations of CSA with depression or depressive symptoms during pregnancy. Findings on the association of CSA with postpartum depression or depressive symptoms were inconsistent; pooled unadjusted and adjusted odds ratios were 1.82 (95% CI 0.92, 3.60) and 1.20 (95% CI 0.81, 1.76). Conclusions-In sum, findings suggest a positive association of history of CSA with depression and depressive symptoms in the prenatal period. Findings on the postpartum period were inconsistent. Clinical and public health implications of evidence from the available literature are discussed, as are desirable study design characteristics of future research.
Reproductive Toxicology, 2015
BACKGROUND-Parabens are used as antimicrobial excipients in some pharmaceuticals. Parabens may ad... more BACKGROUND-Parabens are used as antimicrobial excipients in some pharmaceuticals. Parabens may adversely affect reproduction. OBJECTIVES-Determine whether paraben-containing medication contributes to high urinary paraben concentrations. METHODS-Individuals at a fertility clinic provided multiple urine samples during evaluation/ treatment and reported 24-hour use of medications and personal care products (PCP). Repeated measures models compared specific gravity-adjusted urinary methyl, propyl, and butyl paraben concentrations between samples "exposed" and "unexposed" to paraben-containing medication. RESULTS-Eleven participants contributed 12 exposed and 45 unexposed samples, among which paraben concentrations did not differ. Use within seven hours was associated with 8.7-fold and 7.5-fold increases in mean methyl (P=0.11) and propyl (P=0.10) paraben concentrations, respectively, after adjusting for PCP use. However, these associations decreased to 1.3-fold (P=0.76) and 2.6-fold (P=0.34), respectively, after removal of one influential individual. CONCLUSION-Paraben-containing medications contributed to higher urinary paraben concentrations within hours of use.
American Journal of Hypertension, 2013
Background The global prevalence of chronic noncommunicable diseases (NCDs) is on the rise, with ... more Background The global prevalence of chronic noncommunicable diseases (NCDs) is on the rise, with the majority of the growth occurring among populations in developing countries. Few studies have quantified the health benefits for physical activity among sub-Saharan African adults. We examined associations of physical activity with the prevalence of metabolic syndrome (MetS) and its components in Ethiopian men and women. Methods This cross-sectional study of 1,843 individuals (1,117 men and 726 women) was conducted among working adults (public schools and bank employees) in Addis Ababa, Ethiopia. The study was conducted in accordance with the STEPwise approach of the World Health Organization. Physical activity was assessed using a previously validated Global Physical Activity Questionnaire. MetS was defined according to the International Diabetes Federation criteria. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI). results The odds of MetS was inversely associated with physical activity in men (P trend = 0.02) but not women (P trend = 0.85). Among men, the OR of MetS comparing those with high vs. low levels of physical activity was 0.56 (95% CI = 0.33-0.97). For women, the corresponding OR was 1.07 (95% CI = 0.57-2.01). Physical activity was significantly and inversely associated with high waist circumference and hypertriglyceridemia among men, but no such associations were observed among women. conclusions Higher levels of physical activity were inversely associated with MetS and several individual components among men. No similar trends were observed among women in this cohort, in part because of the small sample size.
Hypertension, 2014
We examined the associations of maternal parity with fetal and childhood growth characteristics a... more We examined the associations of maternal parity with fetal and childhood growth characteristics and childhood cardiometabolic risk factors in a population-based prospective cohort study among 9031 mothers and their children. Fetal and childhood growth were repeatedly measured. We measured childhood anthropometrics, body fat distribution, left ventricular mass, blood pressure, blood lipids, and insulin levels at the age of 6 years. Compared with nulliparous mothers, multiparous mothers had children with higher third trimester fetal head circumference, length and weight growth, and lower risks of preterm birth and small-size-for-gestational-age at birth but a higher risk of large-size-for-gestational-age at birth ( P <0.05). Children from multiparous mothers had lower rates of accelerated infant growth and lower levels of childhood body mass index, total fat mass percentage, and total and low-density lipoprotein cholesterol than children of nulliparous mothers ( P <0.05). They a...
Diabetes & Metabolic Syndrome: Clinical Research & Reviews, 2015
Objective-We sought to evaluate the extent to which major depressive disorder (MDD) is associated... more Objective-We sought to evaluate the extent to which major depressive disorder (MDD) is associated with cardiometabolic diseases and risk factors. Methods-This was a cross-sectional epidemiologic study of 1,924 employed adults in Ethiopia. Structured interview was used to collect sociodemographic data, behavioral characteristics and MDD symptoms using a validated Patient Health Questionnaire-9 (PHQ-9) depression scale. Fasting blood glucose, insulin, C-reactive protein, and lipid concentrations were measured using standard approaches. Multivariate logistic regression models were fitted to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Results-A total of 154 participants screened positive for MDD on PHQ-9 (8.0%; 95% CI 6.7-9.2%). Among women, MDD was associated with more than 4-fold increased odds of diabetes (OR=4.14; 95% CI:1.03-16.62). Among men the association was not significant (OR=1.04; 95% CI: 0.35-3.05). Similarly, MDD was not associated with metabolic syndrome among women (OR=1.51; 95% CI: 0.68-3.29) and men (OR=0.61; 95% CI: 0.28-1.34). Lastly, MDD was not associated with increased odds of systemic inflammation. Conclusion-The results of our study do not provide convincing evidence that MDD is associated with cardiometabolic diseases among Ethiopian adults. Future studies need to evaluate the effect of other psychiatric disorders on cardiometabolic disease risk.
Annals of Epidemiology, 2015
Purpose-We investigated the feasibility of obtaining hair samples from men and women at community... more Purpose-We investigated the feasibility of obtaining hair samples from men and women at community-based barbershops and hair salons for analysis of cortisol and assessed sociodemographic and lifestyle correlates of hair cortisol concentrations (HCC). A total of 102 participants completed the study. Methods-Research staff interviewed participants using a structured questionnaire and samples of hair were collected. HCC were determined using liquid chromatography-tandem mass spectrometry. Age-and sex-adjusted linear regression models were used to evaluate the association of HCC with covariates. Results-Analyses by race/ethnicity showed highest median HCC in Blacks [12.5 (6.9-29.3) pg/mg] followed by Hispanics [10.7 (5.8-14.9) pg/mg], Whites [5.0 (3.8-10.8) pg/mg], and other participants [4.2 (3.3-15.7) pg/mg], p<0.01. Current smokers had significantly higher median HCC [11.7 (8.8-18.9) pg/mg] compared to former smokers [4.6 (3.5-14.6) pg/mg] and those who had never smoked [6.9 (4.7-12.8) pg/mg], p=0.04. After adjustment for age and sex, geometric mean HCC was 0.72 pg/mg lower in dyed hair compared to hair that was not dyed (β=-0.72, SE=0.30, 95% CI:-1.29,-0.15, p=0.02).
Annals of Epidemiology, 2014
Background-We evaluated the extent to which use of a hypothesized imperfect gold standard, the Co... more Background-We evaluated the extent to which use of a hypothesized imperfect gold standard, the Composite International Diagnostic Interview (CIDI), biases the estimates of diagnostic accuracy of the Patient Health Questionnaire-9 (PHQ-9). We also evaluate how statistical correction can be used to address this bias. Methods-The study was conducted among 926 adults where structured interviews were conducted to collect information about participants' current major depressive disorder (MDD) using PHQ-9 and CIDI instruments. First, we evaluated the relative psychometric properties of PHQ-9 using CIDI as a gold standard. Next, we employed a Bayesian latent-class model to correct for the bias. Results-In comparison with CIDI, the relative sensitivity and specificity of the PHQ-9 for detecting MDD at a cut point of ≥10 were 53.1% (95%CI: 45.4-60.8%) and 77.5% (95%CI: 74.5-80.5%), respectively. Using a Bayesian latent-class model to correct for the bias arising from the use of an imperfect gold standard increased the sensitivity and specificity of PHQ-9 to 79.8% (95% Bayesian credible interval (BCI): 64.9-90.8%) and 79.1% (95%BCI:74.7-83.7%), respectively
Sleep and Breathing, 2013
Purpose-This study assessed the association of sleep quality with academic performance among Univ... more Purpose-This study assessed the association of sleep quality with academic performance among University students in Ethiopia. Methods-this cross sectional study of 2173 college students (471 female and 1672 male) was conducted in two Universities in Ethiopia. Students were selected in to the study using a multistage sampling procedure and data were collected through a self administered questionnaire. Sleep quality was assessed using Pittsburgh sleep quality index and academic performance was based on self reported cumulative grade point average. The Student 't' test, Analysis of Variance (ANOVA) and multiple linear regression were used to evaluate associations. Results-We found that students with better sleep quality score achieved better on their academic performance (P-value =0.001) while sleep duration was not associated with academic performance in the final model. Conclusion-Our study underscores the importance of sleep quality on better academic performance. Future studies need to identify the possible factors which influence sleep quality other than the academic environment repeatedly reported by other literature. It is imperative to design and implement appropriate interventions to improve sleep quality in light of the current body of evidence to enhance academic success in the study setting.
Diabetes & Metabolic Syndrome: Clinical Research & Reviews, 2012
Objective-To determine the prevalence of hypertension and diabetes among members of an Ethiopian ... more Objective-To determine the prevalence of hypertension and diabetes among members of an Ethiopian occupational cohort; and to examine the proportion of adults who were aware of their conditions. Methods-A total of 2,153 of subjects were included in this cross-sectional study. The World Health Organization STEPwise approach for non-communicable diseases was used to collect socio-demographic data, blood pressure measures and blood samples from participants. Prevalence estimates for hypertension and diabetes were determined separately. The 95% confidence intervals for prevalence estimates were also determined. Results-The overall prevalence of hypertension was 19.1% (95%CI: 17.1-20.8) and 22% (95%CI: 20.2-23.8) and 14.9% (95%CI: 13.4-16.4) among men and women respectively. The overall prevalence of diabetes was 6.5%(95%CI: 5.4-7.6) and 6.4%(95%CI: 5.0-7.8) and 6.6%(95%CI: 4.8-8.4) among men and women correspondingly. Notably, 15% of hypertensives reported never having had their blood pressure checked prior to the present study examination. Approximately 45% of participants who had their blood pressure checked were never diagnosed with hypertension, but were found to be hypertensive in our study. Approximately 27% of newly diagnosed diabetics (during this study) reported never having a previous blood glucose test. Among those who had their blood glucose assessed prior to this study, 17.4% were found to have diabetes but were never diagnosed. Conclusion-The high prevalence of hypertension and diabetes reported in our study confirms findings from other Sub Saharan Africa countries, and extends the literature to urban dwelling Ethiopians where non-communicable diseases are emerging as a major public health concern.
Annals of Epidemiology, 2013
Placental weight has been associated with mammographic pattern and coronary heart disease in the ... more Placental weight has been associated with mammographic pattern and coronary heart disease in the adult offspring, but the mechanisms are unknown. We evaluated the associations of maternal and cord blood hormones with placental weight in normal pregnancies. Methods: Prospective study of 167 normal singleton pregnancies in Boston, USA and 256 in Shanghai, China. Maternal hormone levels at the 27th gestational week were available for all pregnancies. Cord blood measurements were available for 86 pregnancies in Boston and 104 in Shanghai. Pearson partial correlation coefficients of log-transformed hormone levels with placental weight were calculated. Results: Maternal levels of estriol, testosterone, and progesterone (P < .05) were positively associated with placental weight. There was no such evidence for adiponectin, prolactin, and insulin-like growth factor (IGF)-I. Cord blood steroids tended to be inversely associated with placental weight, the results being statistically significant for testosterone (P < .05). There was a marginally significant positive association of cord blood IGF-I with placental weight. Reported results were adjusted for study center. Conclusions: Placental weight appears to be positively correlated with maternal steroids. Its correlation with cord blood steroids, however, appears inverse, compatible with negative feedback mechanisms. There is also a suggestion for placental weight to be positively associated with cord blood IGF-I.
Physiological Research
Vascular endothelial growth factor (VEGF), a disulphide-linked homodimeric glycoprotein that is s... more Vascular endothelial growth factor (VEGF), a disulphide-linked homodimeric glycoprotein that is selectively mitogenic for endothelial cells, plays an important role in vasculogenesis and angiogenesis. Preeclampsia, a relatively common complication of pregnancy that is characterized by diffuse endothelial dysfunction possibly secondary to impaired trophoblast invasion of the spiral arteries during implantation, has recently been associated with alterations in maternal serum/plasma concentrations of VEGF, and other related growth factors and their receptors. We examined the relationship of maternal plasma VEGF, sVEGF-R1 and PlGF levels to the risk of preeclampsia among women delivering at Harare Maternity Hospital, Zimbabwe. 131 pregnant women with preeclampsia and 175 controls were included in a case-control study. Maternal plasma concentrations of each biomarker were measured using enzymatic methods. We used logistic regression to calculate odds ratios (OR) and 95 % confidence inter...
Physiological Research
Few investigators have simultaneously evaluated leptin, soluble leptin receptor (SLR) and leptin ... more Few investigators have simultaneously evaluated leptin, soluble leptin receptor (SLR) and leptin gene polymorphisms in preeclampsia cases and controls. We examined these three biomolecular markers in 40 preeclampsia cases and 39 controls. Plasma leptin and SLR concentrations were determined using immunoassays. Genotype for the tetranucleotide repeat (TTTC)(n), polymorphism in the 3 -flanking region of the leptin gene was determined using PCR. Alleles of the polymorphism were characterized by size distributions [short repeats (class I); and long repeats (class II)]. Logistic regression was used to calculate odds ratios (OR) and 95 % confidence intervals (CI). Leptin concentrations were higher in our cases than in the controls (53.1 4.7 vs. 17.7+/-2.4 ng/ml, p<0.05). SLR concentrations were slightly lower in our patients than in the controls (25.7+/-1.9 vs. 29.1+/-1.1 ng/ml, p>0.05). Elevated leptin (? 14.5 ng/ml) was associated with a 3.8-fold (CI 1.0-14.4) increased risk; wher...
Physiological Research, 2007
We sought to examine the association between maternal erythrocyte omega-3, omega-6 and trans fatt... more We sought to examine the association between maternal erythrocyte omega-3, omega-6 and trans fatty acids and risk of preeclampsia. We conducted a case-control study of 170 women with proteinuric, pregnancy-induced hypertension and 185 normotensive pregnant women who delivered at Harare Maternity Hospital, Harare, Zimbabwe. We measured erythrocyte omega-3, omega-6 and trans fatty acid as the percentage of total fatty acids using gas chromatography. After multivariate adjustment for confounding factors, women in the highest quartile group for total omega-3 fatty acids compared with women in the lowest quartile experienced a 14% reduction in risk of preeclampsia (odds ratio 0.86, 95% confidence interval 0.45 to 1.63). For total omega-6 fatty acids the odds ratio was 0.46 (95% confidence interval 0.23 to 0.92), although there was suggestion of a slight increase in risk of preeclampsia associated with high levels of arachidonic acid. Among women in the highest quartile for arachidonic ac...
Placenta, 2018
Accumulating epidemiological evidence points to strong genetic susceptibility to placental abrupt... more Accumulating epidemiological evidence points to strong genetic susceptibility to placental abruption (PA). However, characterization of genes associated with PA remains incomplete. We conducted a genome-wide association study (GWAS) of PA and a meta-analysis of GWAS. Participants of the Placental Abruption Genetic Epidemiology (PAGE) study, a population based case-control study of PA conducted in Lima, Peru, were genotyped using the Illumina HumanCore-24 BeadChip platform. Genotypes were imputed using the 1000 genomes reference panel, and >4.9 million SNPs that passed quality control were analyzed. We performed a GWAS in PAGE participants (507 PA cases and 1090 controls) and a GWAS meta-analysis in 2512 participants (959 PA cases and 1553 controls) that included PAGE and the previously reported Peruvian Abruptio Placentae Epidemiology (PAPE) study. We fitted population stratification-adjusted logistic regression models and fixed-effects meta-analyses using inverse-variance weight...
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Papers by Michelle Williams