Thirty studies were included in the review.
Studies tested for: HBOC, 11 prospective studies (n=1,212); HNPCC, six prospective studies (n=578); HBOC and HNPCC, one prospective study (n=87); and AD, one RCT (n=86) and one prospective study (n=76).
Irrespective of disease, the majority of studies found no long term general distress for carriers or non carriers following genetic testing or disclosure of results. There were no studies of AD measuring general distress. In testing for HBOC, there was a trend towards lower short-term and long-term cancer-specific distress regardless of carrier status. Studies assessing cancer-specific distress following HNPCC found either no effect or increased short-term distress that returned to baseline for carriers; non carriers showed either a decrease or no change. There was no effect for specific distress in AD carriers over time. The majority of studies reported no long-term differences in anxiety or depression levels, irrespective of condition or carrier status. The results were conflicting in three studies measuring levels of worry.
Studies tested for: HBOC, seven prospective studies (n=1,516) and two cross-sectional studies (n=140); HNPCC, six prospective studies (n=529); and AD, one RCT (n=111).
Rates of screening behaviour were higher in carriers than non carriers of HBOC and HNPCC in terms of mammography, breast (self and clinical) examination, transvaginal ultrasound, Ca-125 and colonoscopy. Rates of prophylactic surgery for carriers of HBOC ranged from 0 per cent to 51 per cent for mastectomies and 13 per cent to 65 per cent for oophorectomies. One study reported that 9.5 per cent of female HNPCC carriers had undergone a hysterectomy within one year of disclosure. Following genetic testing, 20 per cent to 22.5 per cent of HBOC carriers were using chemotherapeutics to prevent breast cancer. AD carriers were more likely to engage in disease-preventative behaviour. Lifestyle behaviour changes were similar between carriers and non carriers.
Studies tested for: HBOC, three prospective studies (n=422); and HNPCC, four prospective studies (n=449).
There were no long term differences in risk perception in relation to HBOC and HNPCC. Both carriers and non carriers had lower levels than prior to genetic testing.