Risk factors for inguinal hernia in adult males: a case-control study.

BACKGROUND: Inguinal hernia is one of the most common surgical pathologies. Research studies on clinical factors predisposing a person for the development of inguinal hernia, however, remain scarce. The objective of the present study was to evaluate the risk factors for the development of inguinal hernia in adult males, using a case-control design in a hospital-based population.
METHODS: Between January 2002 and January 2004, a total of 1,418 male patients were recruited at the general surgical or hernia clinic of a University-affiliated teaching hospital. Patients were divided into case and control groups according to the presence of a primary inguinal hernia. Each patient was interviewed by a research assistant using a standardized questionnaire. Clinical data were studied by multivariate, logistic regression analyses to identify independent predictors of inguinal hernia in adult males.
RESULTS: Clinical factors associated with the presence of inguinal hernia included a higher work activity index (P = 0.03), a higher total activity index (P = 0.01), a positive family history of inguinal hernia (P < 0.01, odds ratio = 8.73), and chronic obstructive airway disease (P = 0.04, odds ratio = 2.04). After adjustments for the type of hernia, chronic obstructive airway disease was a risk factor only for direct hernia, whereas total activity index and family history of hernia remained significantly related to both direct and indirect hernias. On logistic regression analyses, positive family history of hernia was the only independent predictor for inguinal hernia.
CONCLUSIONS: Family history of hernia was the most important determinant factor for developing inguinal hernia in adult males. A male subject who has a positive family history of hernia is 8 times more likely to develop a primary inguinal hernia.