Incidence of dementia in a Munich community sample of the oldest old

Abstract

In a two-wave community study a representative sample of 402 very old people (older than 85 years) was restudied 1 year later. Four instruments in the clinical examination were used for case identification: (a) the Geriatric Mental State Interview (GMS-A); (b) the Structured Interview for the Diagnosis of Dementia (SIDAM); (c) the Global Deterioration Scale (GDS); and (d) the Mini Mental State Examination (MMSE). The clinical examination was performed by the interviewing physician who made a diagnosis according to DMS-III-R. The focus of the present study is on the (true) incidence of dementia in a representative community sample. The establishment of incidence rates is particularly important for dementia because the prevalence of dementia is affected by the length of survival, which is reduced in dementia and with increasing age. The annual incidence rates per 1000 person years on the basis of the SIDAM DSM-III-R were 116.6 for all cases at risk, 113.6 for those aged 85-89 years, 112.5 for those aged 90-94 years and 235.7 for those aged 95 years and older at first assessment (t1). Incidence rates based on the other methods of assessment are reported. In order to obtain the most meaningful estimate of incidence rates a compound dementia diagnosis was defined. According to this the annual incidence rate per 1000 person years was 144.1 for all persons at risk. The incidence rate tended to be higher in the older-age cohorts: It was 126.2 for those aged 85-89 years, 193.1 for those aged 90-94 years and 295.5 for those aged 95 years and older. In comparison with the literature the incidence rates were high. The results are plausible when the very old age of the sample is taken into account.

The incidence of dementia in an Australian community population: the Sydney older persons study

“…They are similar to ®gures in the Munich Study (Fichter et al, 1996) but higher than those in other studies of`mild plus' dementia (see Table 1). Although a different analytical technique was used, the incidences found in our study were greater than previous Australian incidence ®gures (Snowden and Lane, 1995).…”

Prevalence and Incidence of Clinically Diagnosed Memory Impairments in a Geographically Defined General Population in Sweden

“…This means that the prevalence rate for AD might be approximately 370 rather than 304 cases/ 100,000 persons and the prevalence rate of all forms of memory impairments would [20] 1996 Rural India 60+ Population survey -3.4 41 Rocca et al [21] 1990 Rural Italy 65+ Population survey -8.4 39 Mölsa et al [22] 1982 Finland 65+ Population survey 0.4 2.0 50 Folstein et al [23] 1991 Baltimore, Md., USA 65+ Community survey -4.5 44 Sulkava et al [24] 1985 Finland 65+ Population survey -6.7 50 Li et al [25] 1991 Beijing, China 65+ Population survey 0.3 1.1-1.8 40 Copeland et al [13] 1992 Liverpool, UK 65+ Population survey 0.92 2.4-3.8 68 (moderate-severe cases) Saunders et al [26] 1993 Liverpool, UK 65+ Population survey -4.7 -Morgan et al [27] 1993 Nottingham, UK 65+ Population survey 0.9 --Bickel and Cooper [28] 1994 Mannheim, Germany 65+ Population survey 1.5 -58 Boothby el al. [29] 1994 London, UK 65+ Population survey 2.0 -48 Yoshitake et al [30] 1995 Hisayama, Japan 65+ Population survey 2.0 -38 Prencipe et al [31] 1996 Rural Italy 65+ Population survey -8.0 64 Letenneur et al [32] 1994 Bordeaux, France 65+ Population survey 1.6 -70 Bachman et al [34] 1993 Framingham, USA 65+ Population survey 6.5 -58 Jagger et al [35] 1992 Melton Mowbray, UK 75+ Population survey -5.2 -(moderate-severe cases) Engedal et al [36] 1988 [40] 1989 Iceland 82+ Population survey 1.0 10 -Gussekloo et al [41] 1995 Leyden, The Netherlands 85+ Population survey 6.9 --Fichter et al [42] 1996 Munich, Germany 85+ Population survey 11.6 --Aevarsson and Skoog [16] have been 900 cases/100,000 persons rather than 755. Dementia incidence and prevalence estimates from other studies are summarized in table 6.…”

Dementia in the oldest old: Beyond Alzheimer disease

“…The medical problems facing the oldest old are unique in their scale and complexity and are only recently being studied in depth. Dementia is one of the most serious medical threats facing the oldest old, and although there is considerable variability in studies, several studies have noted that the incidence and prevalence of dementia continues to increase with advancing age, past the age of 90 [1,2,3,4,5]. Partially as a result of global disparities in lifespan, many of the current oldest old cohort studies are being conducted in developed countries in North America, Europe, and Australia [6], which may limit the wider applicability of the results across populations worldwide because of limited genetic and ethnic diversity in these countries.…”