Aging Clin . Exp . Res . 4: 35-41, 1992

Dementia patients with low serum cobalamin concentration: Relationship to atrophic gastritis B. Regland*, C-G. Gottfries*, and G. Lindstedt** *Depa rtment of Psychiatry and Neurochemistry, St. J orqen Hospital , **Department of Clinical Ch emist ry, Sahlgren's Hospital , University of Goteborg , Got eborq , Swed en ABSTRACT. Serum concentrations of group I pepsinogens (pepsinogen-I) and gastrin were determined in patients with dementia disorders in order to assess the relationship, if any, between these indices of gastric mucosal function and serum cobalamin (vitamin Bd levels. A significant positive correlation between pepsinogen-I and B12 and, as expected, an inverse relationship between gastrin and pepsinogen-I concentrations was found, indicating that vitamin B12 deficiency was mainly determined by gastric mucosal atrophy (atrophic gastritis) in this West-Swedish sample of patients with dementia disorders. Patients with low B12 but nor mal gastrin and pepsinogen-I concentrations should, therefore, be further evaluated for possible nutritional deficiency, as well as nongastric causes of poor B12 assimilation from the diet. (Aging Clin. Exp. Res. 4: 35-41, 1992) INTRODUCTION Th e possible causal relationship between senile dementia and low serum cobalamin (vitamin Bd concentrations has been discussed since the ea rly 1950s when serum B12 assay techniques were developed (1, 2). Our psychiatric dep artment recently reported that 23% of patients with senile dem entia have low «130 pmol/L) serum vitamin B12 levels (3). It is not known whether low B12 concentrations are associated with metabolic cell disturbance in dem entia pat ients, but results of serum homocyst eine and serum (or urinary) methylmal-

onate assa ys in patients with neurological disorders show that such disturbanc e can be ob se rved even in peopl e with serum B12 values well above the lower reference limit. A low serum B12 level might result from poor dietary intake, malabsorption, or low protein binder concentration. While nutritional depletion is conside red responsible for many of the low vitamin B12 values found in elderly hospital inpatients (4) and psychiatric pat ients (5), the low values in the latter are thought to be secondary to ment al illness, leading to apat hy and loss of appetite. Redu ced B12 absorption from the diet might be du e to an insufficiency of the gastric or intestinal mucosa, poor availability of active pan creatic enzymes , or the presenc e of intestinal microorganisms or parasites. Therefore, an evaluation of the underlying etiology is of interest, not only for a better und erstanding of dementia disorders, but also for a rational treatment of the patients. Norm al gastric mucosa secretes hydrochloric ac id and intrinsic factor, and both are important for vitamin B12 digestion and absorption. Gastric mucosa function can be assessed by determining gastric acid secretory capacity, either directly by examining biopsy spe cimens at the micr oscope, or indirectly , by measuring blood levels of pepsinogens and gastrin. The serum co nce ntra tions of group-I pepsinogens (pepsinogen -I) , which are produced by the fundic mucosa, reflect both gastric mucosal morphology (6-8) and ca pacity for gastric acid secretion (9,

Key words: Atro phic gastritis, dementia, gas trin, pepsinogen, vitamin B12 deficiency. Correspondence: Dr. Bjorn Regland, Department of Psychiatry and Neurochemistry, Molndal Hospital, 5-43180 Molndal, Sweden. Received J anuary 31, 1990; acce pted Novem ber 20, 1990.

Aging Clin. Exp. Res., Vol. 4, N. 1 35

B. Regland, C-G. Gottjnes, and G. Lindstedt

10), as evidenced by the low values found in patients with atrophic gastritis compared to those in patients with a normal gastric mucosa. However, a discrepancy was noted in superficial gastritis, in which high serum pepsinogen-! concentrations were observed together with a reduced acid-secretory capacity (7, 11). Serum gastrin concentrations are high in cases with antrum-sparing atrophic gastritis, and markedly elevated serum gastrin concentrations occur in 5-10% of elderly people (12). The aim of this study was to ascertain whether gastric mucosal insufficiency could constitute a contributory factor to low serum B12 concentrations in dementia patients. PATIENTS The study included one series of 57 consecutive patients (39 women and 18 men) admitted to a psychogeriatric diagnostic unit (group A). Senile dementia of Alzheimer type (SDAT) was diagnosed in 24, Alzheimer's presenile dementia (AD) in 6, and dementia of probable vascular origin (VD) in 12 cases; among the other patients (classified as VAR!A), 5 had suspected dementia, 3 a confusional state, 2 alcohol dementia, 1 an unspecified encephalopathy, 3 depression, and 1 a neurotic disorder. One of the patients with SDAT had concomitant dermatitis herpetiformis, and was excluded as the small-intestinal mucosal lesions often found in this disorder, similar to those in coeliac disease, may contribute to vitamin B12 malabsorption. No other exclusions were made. To further elucidate pepsinogen-! and gastrin levels in patients with low serum B12 levels,

another series of 23 consecutive outpatients (14 women and 9 men), fulfilling criteria for SDAT along with serum B12 concentrations 250 pmoljL (N = 21). Shaded area indicates the expected relationship between the two parameters with the decision limits discussed in the text.

Figure 2 and Figure 3 present the serum concentrations of pepsinogen-I and gastrin, with separate diagrams for the groups with B12 below or above 250 pmol/L. There was a significant and negative correlation between pepsinogen-I and gastrin in demented patients with low B12 levels (r = 0.63; p100 pmol/L were found in the group with B12 below 250 pmol/L as were also the majority of the patients with serum pepsinogen-I concentrations

Dementia patients with low serum cobalamin concentration: relationship to atrophic gastritis.

Serum concentrations of group I pepsinogens (pepsinogen-I) and gastrin were determined in patients with dementia disorders in order to assess the rela...
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