The Eyes and Ears of the World of Function

To the Editor:-The impact of sensory deprivation on the quality of life in the elderly has been extensively studied, leading to contradictory conclusion^. '-^ Bess et al, in a recent issue of this journal, presented the results of cross-sectional research showing that hearing impairment is an important determinant of function in older p e ~ p l e . ~ They performed a multivariate analysis to assess the effects of hearing impairment, detected with pure-tone audiomehy, on functional, psychosocial, and overall scores of the Sickness Impact Profile (SIP), which was self-administered by 153 elderly patients screened in primary-care practice. In our opinion, two points must be carefully considered in connection with Bess et al’s findings, as the authors themselves recognize in their conclusions. First, data were obtained in a primary-care setting that is not necessarily representative of the elderly living in the community. Second, hearing impairment was taken into account, whereas visual function was considered only as a confounding variable and not as a potential source of sensory deprivation. We believe the effects of visual impairment on functional parameters equally deserve appropriate investigation. Our group camed out a multidimensional study on a large community elderly population, homogeneous for age (7075 years) and living place.6 We interviewed and carefully evaluated 1201 subjects (approximately two-thirds female), living at home, who represented 92% of the elderly inhabitants of the area. Among the various parameters assessed, both vision and hearing efficiency were examined and considered so as to divide the total sample into four subgroups: subjects with both hearing and vision adequate (VA-IA) (78.9’70), those with either hearing (VA-HI) (9.8%) or visual (VI-HA) (8.8%) deficit, and those with both hearing and vision impairment (VI-HI) (1.79’0). Examination of sensory function was camed out with the subject’s usual visual or auditory aid in place because we were not interested in qualifying the prevalence of sensory decay, but in assessing the functional impairment in a daily-living setting. Demographic data were not different between the four subgroups in a one-way analysis of variance. The assessment was comprehensive, including physical, functional, psychosocial, and medical variables that were subsequently related to sensory deprivation. ’ We performed the Activity of Daily Living scale of Katz8 and the Instrumental Activity of Daily Living scale of Lawton? Both scales were used to divide the sample into two classes: zero or one function lost (idependent people), two or more functions lost (dependent people). Social interactions were assessed through the SELF scale of Linda; subjects were divided based on their total score into three groups-low, middle, and high social satisfaction. Table 1 shows that the presence of a single sensory deficit, either hearing or vision, is associated with a significant increase in the percentage of subjects with impairment in functional and social levels. Furthermore, with double sensory deprivation there is no additional deterioration of functional and social scores. There were no differences due to gender. Our data support and amplify the results of Bess et al. In their model, the variance attributed to hearing accounted for 24%, 746, and 6% of the total variance in the functional, psychosocial, and overall SIP scale scores; a multiple sensory assessment would probably have accounted for a higher percentage of the total variance. We recommend simultaneous assessment of vision and hearing.