Illicit drug use, early age at first use and risk of premenstrual syndrome: A longitudinal study.
BACKGROUND
Premenstrual syndrome (PMS) is common among women of reproductive age. Limited studies have investigated the long-term association between illicit drug use and PMS.


METHODS
The 1973-1978 cohort from the Australian Longitudinal Study on Women's Health, a prospective cohort study, was followed up for 13-year from 2000 to 2012. Data were collected through self-reported questionnaires on all variables, including PMS, illicit drug use and a range of sociodemographic, lifestyle, reproductive and psychological factors.


RESULTS
When the women were 22-27 years of age, over 40% use illicit drug in the last 12 months, 9% first used drug before age 15 years and approximately 35% reported PMS. Over the study period, the prevalence of drug use in the last 12 months declined whereas that of PMS remained fairly stable except an increase when they were 34-39 years old. Generalised estimating equations analysis showed that, compared to never drug users, significantly higher odds of reporting PMS were detected for illicit drug use in the last 12 months: multiple drugs (odds ratio (OR) 1.31, 95% confidence interval (CI) 1.21, 1.43), exclusive marijuana (OR 1.23, 95% CI 1.08, 1.40). A higher odds of PMS was identified for age at first drug use before 15 years (OR 1.20, 95% CI 1.03, 1.40).


CONCLUSIONS
Illicit drug use in the last 12 months, especially early age at first use and multiple drug use, is associated with increased risk of PMS. However current study is unable to prove causality.
Centre for Longitudinal and Life Course Research, School of Public Health, The University of Queensland, Brisbane, Australia; Level 3 Public Health Building, Herston Road, Herston, Brisbane, QLD 4006 Australia. Electronic address: h.ju@uq.edu.au.
Hong
H
Ju
Centre for Longitudinal and Life Course Research, School of Public Health, The University of Queensland, Brisbane, Australia; Level 3 Public Health Building, Herston Road, Herston, Brisbane, QLD 4006 Australia. Electronic address: m.jones@sph.uq.edu.au.
Mark
M
Jones
Centre for Longitudinal and Life Course Research, School of Public Health, The University of Queensland, Brisbane, Australia; Level 3 Public Health Building, Herston Road, Herston, Brisbane, QLD 4006 Australia. Electronic address: g.mishra@sph.uq.edu.au.
Gita D
GD
Mishra
D000328:Adult; D001315:Australia / Q000453:epidemiology; D055030:Drug Users / Q000523:psychology / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D011293:Premenstrual Syndrome / Q000150:complications / Q000453:epidemiology* / Q000209:etiology* / Q000523:psychology; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D019966:Substance-Related Disorders / Q000150:complications* / Q000453:epidemiology* / Q000523:psychology; D011795:Surveys and Questionnaires; D055815:Young Adult
Illicit drugs; Longitudinal studies; PMS; Premenstrual syndrome; Substance use