Aim To investigate whether people on a waiting list for cochlear implantation are more likely than those who have cochlear implants to suffer from illnesses which are potentially mediated by stress. Method A questionnaire, designed to assess the presence, persistence, and medication use associated with stress-related illnesses, was administered to two groups: those on a waiting list for cochlear implantation and adult users of cochlear implants. Results Those on the cochlear implant waiting list had significantly poorer health as indicated by: a greater number of conditions experienced in the past year, longer illness length when affected by a condition, medication use for a greater number of conditions, and poorer mental health. Conclusion There are lengthy waiting lists for adult cochlear implantation. The need to wait and the lack of a known date for surgery, in combination with having a profound hearing loss is likely to result in chronic stress. Chronic stress may increase the risk of physical and mental illness via physiological systems which mediate response to environmental threats. Cochlear implantation may alleviate chronic stress in people on the waiting list, and these findings support the hypothesis that this influences physical health.