Objective: To assess whether tobacco smoking is associated with Premenstrual Syndrome (PMS) and its most severe form, Premenstrual Dysphoric Disorder (PMDD).
Design: Case-control study with incident cases using the Spanish public healthcare system.
Setting: 3 major public hospitals and one family counseling and planning center.
Population: Women consulting for troubles related to menstruation and for other motives such as screening for uterine cancer, contraception counseling or desire for pregnancy.
Methods: Logistic regression.
Main outcome measures: Odds Ratios of PMS and PMDD.
Results: 285 incident PMS cases and 285 age-matched controls on the one hand, and 88 incident PMDD cases and 176 controls on the other hand participated in the study. The odds of premenstrual disorders was higher in current smokers compared with never smokers: Odds Ratio (OR) = 1.78, 95% Confidence Interval (CI): 1.20-2.63 for PMS and OR = 2.92, 95%CI: 1.55-5.50 for PMDD. For PMS, women who smoke 1 to 5 cigarettes/day presented an OR = 2.82, 95%CI: 1.57-5.06 and those who smoke more than 15 cigarettes/day an OR = 2.52, 95%CI: 0.99-6.40. Compared to non-smokers, current and ex-smokers who smoked < 3 pack-years presented an OR = 1.79, 95%CI: 1.04-3.08 for PMS, and an OR = 3.06, 95%CI: 1.27-7.35 for PMDD. Smokers of 3 to 8 pack-years presented an OR = 2.34, 95%CI: 1.33-4.13 for PMS and OR = 3.56, 95%CI: 1.55-8.17 for PMDD. These results were confirmed by the exposure-effect curve obtained from a cubic spline model.
Conclusions: This study shows that smokers are more likely to develop PMS and PMDD.