Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis.

Previous studies have investigated the close association that exists between CAG repeat number and the age at onset in SCA2 = spinocerebellar ataxia type 2. These studies have focused on affected individuals. To further characterize this association and estimate the risk of a carrier developing SCA2 at a particular age as a function of a specific CAG repeat size, we have analyzed a large group of 924 individuals, including 394 presymptomatic and 530 affected individuals with a CAG repeat length of 32-79 units. Using a Kaplan-Meier survival analysis, we obtained cumulative probability curves for disease manifestation at a particular age for each CAG repeat length in the 34-45 range. These curves were significantly different (p < 0.001) and showed small overlap. All these information may be very valuable in predictive-testing programs, in the planning of studies for the identification of other genetic and environmental factors as modifiers of age at onset, and in the design of clinical trials for people at enlarged risk for SCA2.

Antigliadin antibodies in Cuban patients with spinocerebellar ataxia type 2.

OBJECTIVE: To evaluate the significance of antigliadin antibodies (AGA) levels for spinocerebellar ataxia type 2. METHODS: We determined AGA levels in 64 patients with spinocerebellar ataxia type 2 and in 65 healthy matched controls. The clinical assessment was carried out using the International Cooperative Ataxia Rating Scale and CAG repeat number was assessed by PCR. RESULTS: Antibodies were positive in 23.4% of the ataxia patients and 9.09% of the controls. Statistical comparison using chi2 test with Yates's correction reveals significant differences between these two groups (chi2 = 3.94; p = 0.047). The same was obtained for strongly positive AGA (chi2 = 4.62; p = 0.032). There were no significant differences between AGA positive and AGA negative patients in age at onset, disease duration, ataxia score or CAG repeat number, neither in the prevalence of gastrointestinal symptoms, prevalence of wheat intolerance or body weight. CONCLUSIONS: These results demonstrate an association between antigliadin antibodies serum levels and SCA2. However, more work has to be done to clarify the clinical consequences of such an association.

Antigliadin antibodies in Cuban patients with spinocerebellar ataxia type 2

Antibodies were positive in 23.4 percent of the ataxiapatients and 9.09 percent of the controls. Statistical comparisonusing x2 test with Yatess correction reveals significantdifferences between these two groups (x2=3.94; p=0.047). The same was obtained for strongly positiveAGA (x2=4.62; p=0.032). There were no significant differences between AGA positive and AGA negativepatients in age at onset, disease duration, ataxia score orCAG repeat number, neither in the prevalence of gastrointestinal symptoms, prevalence of wheat intolerance or body weight. These results demonstrate anassociation between antigliadin antibodies serum levels and SCA2. However, more work has to be done to clarify the clinical consequences of such an association...(AU)