Data highlight the need for patient and provider education
“This study furthers our knowledge regarding long-term complications associated with the frequent pregnancy complication of preterm delivery,” Stephen S. Crane, MD, an ob.gyn. and maternal-fetal medicine specialist in private practice in Orlando, said in an interview. “Cardiovascular disease is the leading cause of death and often goes unrecognized in women. There are shared risk factors among women and men for developing CVD, the most common being hypertension. However, women have the unique risk factor of pregnancy and its attendant complications including preeclampsia, glucose intolerance, and preterm delivery. Hypertensive disorders in pregnancy often lead to indicated premature delivery, and are associated with development of chronic hypertension and subsequent CVD. However, prior data suggest that preterm delivery itself is a risk factor for developing chronic hypertension later in life.
“The current study, which evaluates one of the most complete population data sets with up to 43 years of follow-up, is the first to assess for familial determinants by cosibling analysis, and supports preterm delivery as an independent risk factor for the development of hypertension,” he said. The study results illustrate that this risk is longstanding, and that recurrent preterm birth further increases the risk of developing hypertension.
Dr. Crane said he was not surprised by the study findings, given that inflammatory processes have been linked to the development of hypertension and CVD. “Similarly, inflammatory processes have been implicated in the pathophysiology of preterm labor and inflammatory cytokines may also play a role in normal term labor. Therefore, it is not surprising that preterm delivery would be a marker for the risk of development of hypertension, as both may be responses to underlying inflammatory processes. Identification of these underlying inflammatory processes and methods for prevention will be critical if we are to decrease both the incidence of preterm birth and CVD.
“As prenatal care may be the only medical care women obtain, it is important to take this opportunity to educate patients regarding their long-term risks of developing hypertension and the need for long-term follow up. Interventions that may help reduce the risk for recurrent preterm birth and long-term risks for developing hypertension and CVD include weight loss, increased activity, and smoking cessation; the resources to achieve these goals need to be shared with patients,” he said.
“Knowledge deficits both on the part of the provider and patient may be a significant barrier to intervention that may be overcome with improved education,” said Dr. Crane. “Care providers need education regarding the long-term risks associated with a history of preterm delivery in order to better educate their patients regarding both prevention of recurrent preterm birth and the development of hypertension and CVD.” However, socioeconomic status, education level, and the inability to obtain further health care remain common barriers to intervention for many women.
“Additional research is needed to identify the causes of inflammatory processes leading to preterm delivery and risks for hypertension and CVD,” said Dr. Crane. “Only after the causes are identified can treatments be sought to successfully treat these conditions.”
The study was supported by the National Heart, Lung, and Blood Institute at the National Institutes of Health; the Swedish Research Council; the Swedish Heart-Lung Foundation; and an Avtal om Läkarutbildning och Forskning (Agreement on Medical Training and Research) (ALF) project grant from Region Skåne/Lund University. Neither the researchers nor Dr. Crane had any financial conflicts to disclose.