Limited conclusions can be drawn about lifestyle interventions in women of reproductive age because of the small number of included RCTs, the heterogeneity of interventions examined, and the lack of consistent findings across studies. Lifestyle interventions improved dyslipidemia in 10 of 18 studies and hypertension in 4 of 9 studies. Stronger benefit was seen on levels of TC and LDL-C than on HDL-C or TG. Improvements in systolic blood pressure were seen in 3 of 9 studies that examined blood pressure changes. Diastolic blood pressure improved in 4 of 9 studies. Follow-up tended to be short-term (1-2 y), and most samples comprised healthy women of reproductive age.
Our assessment of the effectiveness of lifestyle intervention is consistent with reviews conducted on low-risk populations. A systematic review of lifestyle interventions among healthy adult men and women also concluded that lifestyle interventions offered marginal short-term benefit on blood pressure and, to a lesser degree, lipids (52
). Two meta-analyses examined the effect of aerobic exercise on blood pressure and found modest reductions among normotensive, mostly older women (13
). The effects of lifestyle interventions on lipids appear to be strongest for LDL-C and TC and weaker for any benefit to HDL-C or TG, consistent with similar investigations (14
). Previous reports indicated mixed findings regarding the effect of exercise on TG and HDL-C levels; improvements were reported for physically inactive subjects primarily. Indeed, that was the case for the studies in which we found improvements in TG and HDL-C (38
). Finally, exercise duration may be the most important predictor of change to HDL-C (55
); the 2 studies reporting improvements in TG and HDL-C levels had the longest intervention duration (1-2 y).
The review of guidelines revealed that diagnostic criteria and screening recommendations for dyslipidemia vary. Optimal screening tests include measurement of total and HDL-C levels or apolipoproteins without fasting and without regard to triglycerides (49
). Updated NHLBI guidelines for hypertension and dyslipidemia screening are anticipated in 2012.
We found only 1 study that examined prevalence of hypertension screening and another for dyslipidemia screening among women of reproductive age. One study reported 82% of women of reproductive age received hypertension screening within the preceding year (50
), which is higher than a current estimate of 75% screened (according to unpublished National Health Interview Survey [NHIS] data analyses, women aged 14-44 y, 2008). However, nearly 90% of women of reproductive age get hypertension screening within the recommended interval of every 2 years (NHIS data analyses, 2008). Kuklina et al also reported that 49% to 69% of women aged 20 to 45 years had their cholesterol checked in the previous 5 years (51
), which is consistent with estimates from 2008 NHIS unpublished analyses for the same population (64%). The lack of consensus among dyslipidemia screening guidelines may be the reason for lower screening rates in this population.
Few studies provide detailed examination of hypertension and dyslipidemia screening prevalence among women of reproductive age. Perhaps this gap in the literature exists because young people tend to be healthy and the age gradient is marked in these conditions, so women of reproductive age have not been considered a target for screening surveillance. However, identification of high-risk subpopulations and clarification of screening recommendations may prevent the onset of hypertension, dyslipidemia, and other chronic conditions such as diabetes among those at increased risk for CVD.
Substantial body of evidence establishes that diet and exercise improve hypertension and dyslipidemia, but that literature is predominantly based on studies of men and older women. Individual study samples included in this review may lack the power to detect the benefits of lifestyle interventions among healthy populations. For example, pooled results among RCTs that enrolled healthy older women detected significant effects between aerobic exercise and blood pressure, although the individual RCT findings were not significant (53
). Pooling studies in meta-analyses can add the needed statistical power to detect modest short-term benefits of lifestyle interventions, but not enough studies are focused on women of reproductive age to do this.
Women of reproductive age are a population in need of CVD screening and early intervention. Lifestyle modifications are appropriate initial therapies for most patients and may reduce CVD risk through mechanisms other than lowering LDL-C or blood pressure, such as through smoking cessation, weight reduction, and increased physical activity (48
). Moreover, a dose-response effect of physical activity on CHD risk suggests that higher intensity exercise conveys greater benefit (57
To our knowledge, this is the first published systematic review of RCTs examining the effects of lifestyle interventions on hypertension, dyslipidemia, or CVD among women of reproductive age. Its strengths include a review of the grey literature, report of study flow, and assessment of the quality of included RCTs. The geographic breadth of included RCTs spanned Africa, Asia, Europe, Oceania, and North and South America. Studies from Europe and North America were most prevalent; thus, results are generally representative of women of reproductive age from those regions. However, racial composition was addressed in only one-third of the studies (20
), and only 5 included minority women (20
). Given racial differences in hypertension and dyslipidemia screening (50
) and the need to explore lifestyle interventions' benefits in high-risk subpopulations of women of reproductive age, future RCTs should recruit sufficient numbers of at-risk women of reproductive age, including African American and obese women. The main limitation of this review is the possibility of missed studies. We did not search non–English-language literature, and it is possible that RCTs have been published in other languages. We also may have missed potentially relevant studies that are not indexed in PubMed.
Given the reproductive health importance of identifying hypertension or dyslipidemia among women of reproductive age, surveillance of hypertension and dyslipidemia screening in this population is needed. Lifestyle interventions may offer modest short-term benefits for reducing blood pressure or lipids among healthy women of reproductive age that may lead to larger long-term benefits. Further research is needed to clarify predictors of and barriers to cholesterol screening in this population and to investigate the long-term benefits of lifestyle interventions for women of reproductive age.