The Passo Fundo Cohort Study: design of a population-based observational study of women in premenopause, menopausal transition, and postmenopause

Abstract

Background: The Passo Fundo Cohort Study (PFS) is a population-based longitudinal observational study of pre-, peri-, and postmenopausal women that has been ongoing since 1995 in Passo Fundo, a city in southern Brazil. This paper describes the rationale and design of the PFS and summarizes objectives and procedures that have been updated during follow-up. Methods/Design: Women in the PFS have been followed for a variety of diseases that are frequent in menopause. Sampling was conducted in 154 randomly selected census divisions (geographical subdivisions of the city as defined by the Brazilian Institute of Geography and Statistics). One block in each census division was chosen by lot and two women were randomly selected for interview in each block. The first cycle, conducted between 1995 and 1997, included a representative sample of 298 women aged 35 to 55 years. In the second cycle, conducted between 2001 and 2002, additional participants were enrolled based on the same sampling strategy used in 1995, for a final sample of 358 women. In 2010, a third follow-up was initiated, when all 358 participants or their relatives were located. Participants completed a standardized questionnaire on demographic and socioeconomic characteristics. They also answered questions about lifestyle, medical and reproductive characteristics, sexual life, hormone therapy and mental aspects by using validated instruments. Physical activity was assessed and anthropometric measurements, blood sampling and pelvic ultrasound examination were performed. In the third cycle, bone mineral density by dual-energy X-ray absorptiometry and abdominal fat and coronary artery calcium score by computed tomography were also determined.

Prevalence and risk factors associated with diabetes mellitus among middle-aged women in southern Brazil: a population-based study

“…The rationale and design of the study have been described previously. 11 Briefly, in the first cycle, the sample size was based on a population of 16,958 women between 35 and 55 years of age. The sample size for prevalence studies was calculated based on the assumption that 20% of premenopausal and perimenopausal women would have climacteric symptoms, with a 15% error and 95% CI.…”

“…Participants were interviewed and completed a questionnaire that had been pretested and validated in previous studies. [11][12][13][14][15] The questionnaire covered demographic characteristics (age, self-reported skin color), education (assessed through the number of years of schooling completed), gynecologic data (age at menarche, menstrual frequency, age at menopause, parity, previous gynecologic surgery), use of HT, and use of hormonal contraceptives. Employment status was categorized as currently working or not working based on the answer to the question "Are you currently working?…”

“…18,19 Menopausal status was based on the characteristics of menses or time since amenorrhea: premenopause was defined as usual menstrual frequency or flow at the time of the study; perimenopause was defined as changes in menstrual frequency or flow right before the study; and postmenopause was defined as 12 or more months of amenorrhea occurring naturally or because of surgical intervention (eg, bilateral oophorectomy). 11,20,21 A hysterectomy category was created for women who had had a hysterectomy and in whom menopausal status could not be determined.…”

“…Participants were classified as physically inactive (<6,000 steps/d) or active (≥6,000 steps/d) based on the classification proposed by Thompson et al 23 Participants were instructed not to change their PA habits during the study. 11,15…”

C-reactive protein gene rs1205 polymorphism is associated with low-grade chronic inflammation in postmenopausal women

“…The second study [31] was cross-sectional in design (third field visit) and nested in a longitudinal population-based study of menopausal status that aims to assess cardiovascular risk among pre-, peri-, and postmenopausal women through habitual physical activity, coronary artery calcium, abdominal fat and anthropometric measurements. The detailed study protocol has been described elsewhere [32]. Only data from postmenopausal women were included in the present study.…”