While psychological illness and alcohol consumption can reduce treatment response in patients with chronic hepatitis C, the effect of other behavioral and lifestyle factors remains unclear, according to a recent study.
Researchers performed a systematic review of 34 studies, conducted between 1994 and 2011, evaluating the impact of social, lifestyle and psychological factors on sustained virologic response (SVR) to treatment for chronic hepatitis C (CHC).
Across 10 of 12 studies assessing the impact of psychological factors, SVR rates were similar between patients who did and did not have psychiatric illness, in the event that participants continued to receive psychological therapy. Patients with psychological illnesses displayed treatment discontinuation rates of 14% to 48% (compared with 0% to 30%) across 11 studies.
In six of seven studies, increased weight and BMI were associated with reduced likelihood of SVR. One study assessing diet quality indicated that patients who were nonresponsive to treatment consumed fats, polyunsaturated fatty acids and carbohydrates in larger amounts than patients who achieved SVR. The investigators concluded, however, that the impact of dietary intake on SVR was unclear, due to an insufficient number of studies.
In 10 studies, quantities of alcohol consumed had a direct effect on SVR: An excess of 70 g per day reduced the likelihood of achieving SVR, while consumption of less than 30 g per day did not have an impact. Treatment discontinuation rates also were higher among participants who consumed more than two drinks daily, compared with nondrinkers (44% vs. 26%; P=.0001).
“Overall, the number of studies examining the effects of psychological, lifestyle and social factors on CHC treatment response was low, with no studies that met inclusion criteria looking at exercise, education, socioeconomic status or coping skills,” the researchers wrote. “The lack of consistency in assessing the data across the studies highlights the need for the operationalization of variables using consistent measurement standards, such as SVR. Therefore, future research should standardize the variables being examined, to allow valid comparison of outcomes across studies.”