Incorporating a patient's family history into the cardiovascular (CV) risk assessment mix can help identify more patients with risk and could improve prevention tactics, according to a study published in the Feb. 21 issue of the Annals of Internal Medicine.
“Family history is a recognized risk factor for many chronic diseases and is traditionally part of history taking in clinical practice,” according to background information from the article. “Family history is rarely used in isolation but instead is part of a multifactorial risk assessment, such as for coronary heart disease (CHD).”
Because previous data examining the value of collecting family history to predict CV risk is limited, Nadeem Qureshi, DM, of the University of Nottingham, Nottingham, U.K., and colleagues, set out to assess the feasibility and worth of collecting a patient’s family CHD history to assess CVD risk.
To do so, the authors performed a cluster randomized, controlled trial of 24 family practices in the U.K., which included 748 patients between the ages of 30 to 65 years who were not previously diagnosed with CV risk. The study was conducted between July 2007 and March 2009.
The researchers used the proportion of patients with high CV risk—a 10-year risk of 20 percent of more—as the study’s main endpoint. The 24 practices were split into two groups, those that were the control group (12 practices), and those that modeled as the intervention group (12 practices collected family history).
There were 358 patients in the control group and 390 in the intervention group. The researchers identified 105 patients as having a high CV risk. The mean increase in proportion of patients classified as having high CV risk was 4.8 percentage points in the intervention group and 0.3 percentage points in the control practices. This 4.5 percentage point difference between the two groups continued post-adjustment for participant and patient characteristics.
The number of patients at high risk in the interventional group increased 40.8 percent, from 49 to 69, after family history from the questionnaires was incorporated. In both groups, nearly 5 percent of patients had a family history of premature CHD. However, this increased to 29.2 percent in the intervention group when family history was obtained.
Between baseline and six months, medication use had changed among patients. For example, self-reported aspirin use was greater in the intervention group compared with the control group, 29 to 43 patients vs. 19 to 25 patients. At six months, 16.2 percent of patients in the control group received statins compared with 14.4 percent in the intervention group.
“We found that adding systematic collection of family history improves the identification of persons with high cardiovascular risk in primary care practice,” the authors wrote. “Compared with practices that offered the usual Framingham-based assessment, the intervention practices identified an additional 5 percent of persons with high cardiovascular risk.”
The authors noted that being identified as having a high CV risk could lead to changed behavior and an improved lifestyle. In fact, the researchers said that prescribing statins could reduce CHD events by more than 30 percent, and could do so in a cost-efficient manner.
But while this information may be beneficial to the future of cardiac care, the authors noted that it will be difficult to collect these data, and a more important question may be what is the best approach to collect these data?
“Although use of family history may assist in directing preventive efforts to persons at greatest cardiovascular risk, further research could assess whether more intensive interventions, including counseling that emphasized familial predisposition, would improve objectively measured risk-reducing behavior and clinical outcome,” the authors summed.
The authors said that this cost-effective approach to identifying patients most at risk for CV disease could help thwart the disease and play a major role in preventive care.
"Count me a skeptic when it comes to genetic technologies in primary care practice—and my skepticism is not ill-informed," wrote Alfred O. Berg, MD, MPH, of the University of Washington in Seattle, in an accompanying editorial. "How nice to be shown that I might be wrong on both counts by a single study," Berg said, referring to Qureshi et al's study.
However, Berg noted that a study comparable to this one would be difficult to conduct in the