Adults with severe to profound deafness suffer from high levels of psychological distress, and experience difficulties in accessing health care, a review has found.

Relevant studies published since 2005 were identified by searching a number of databases: Medline, Embase, PsycINFO, PSYNDEXplus, PsycCritiques, PsycEXTRA and the Cochrane Database of Systematic Reviews.

This was not a systematic review: methodological quality was not assessed and inclusion criteria were not defined. Only four studies of the prevalence of mental health problems in severely deaf adults were identified: the authors suggest that the lack of studies may reflect the isolation of the deaf community.

Three of the four studies used the GHQ-12 as a measure of psychological distress. This identifies symptoms of anxiety, depression, social dysfunction and loss of confidence. A score > 4 is considered to denote a ‘case’ of psychological distress.¹

The studies from New Zealand and Austria both reported very high mean GHQ-12 scores, which were above the threshold for caseness, 4.82 (SD 2.57) and 4.38 (SD 2.53) respectively. Only the Austrian study included a control group, with a mean GHQ-12 score of 1.16 (SD 2.10). The Dutch study reported lower mean GHQ-12 scores of 1.5 and 2.4 (SD 2.4 and 3.4) for pre- and postlingually deaf adults respectively.² The remaining study, from Norway, used a three-item postal survey and found that deaf adults had significantly more anxiety and depression symptoms than a sample from the hearing population.

There are a number of reasons why severely deaf people may be more likely to suffer from common mental disorders (CMDs).

Many of those with prelingual deafness have communication problems, with secondary psychosocial difficulties. Those with postlingual deafness are more likely to perceive their deafness as a handicap and a loss, which may explain the higher levels of psychological distress in this group.² Deafness may be associated with other disabilities e.g. learning disability, and deaf children are more likely to suffer from abuse.

Most patients with CMDs do not receive effective treatment, either because of failure to seek help, failure of GPs to recognise their CMD, non-adherence to, or early cessation of, treatment.

Outcomes are likely to be even worse for deaf patients. They may be less likely to seek help because of problems accessing information regarding mental health, difficulties making appointments or previous negative experiences at the surgery.

Recognition of CMD may be hindered by communication problems: lip reading is tiring and relies on guesswork; communication by written notes is unsatisfactory particularly when patients have literacy problems; interpreters are often unavailable, and use of family interpreters compromises patient autonomy.³

Effective treatment may be prevented by a misunderstanding of dosage instructions³ or difficulty accessing psychological therapies. There is also a risk of misdiagnosis: doctors may misconstrue visual communication as evidence of agitation, or withdrawal from communication as evidence of psychomotor retardation.

The authors provide guidance on effective communication with deaf patients. We should ask how they wish to communicate; if their preference is for sign language, we should make every effort to provide a qualified interpreter. Effective communication is time-consuming and we should provide longer consultations.

Dr Phillip Bland