Hypertension in classical trigeminal neuralgia: a risk factor to its occurrence or a concurrent condition?

To explore whether hypertension (HTN) is a risk factor for the development of classical trigeminal neuralgia (CTN). In a roughly designed study, 500 patients diagnosed with CTN were brought into the research group, and the control group was composed of the same number of age- and sex-matched subjects without CTN. Characteristics of CTN cases were analyzed. The difference in prevalence of HTN between the research and control groups was calculated using the Chi-square test. In a further study, for CTN cases both suffering from HTN, only those whose onset of HTN earlier to that of CTN were selected, the different prevalence of HTN in the remaining CTN cases and their controls was also counted using the Chi-square test. Females were more affected by CTN with a peak age between the fifth and seventh decades; right-side involvement and mandibular branch affliction occurred at a greater frequency. In the roughly designed study, 48.6% of CTN patients were diagnosed as having HTN compared to 24.6% of the control group. Statistical significance of the different prevalence of HTN between the two groups was observed (P < 0.001). In the more strictly designed study, 389 CTN cases were included in which 33.9% of patients were involved in HTN versus 24.7% of their controls. The increased incidence of HTN in the CTN patients was also statistically significant (P = 0.006). The risk rate of developing CTN in patients with HTN was 1.38 (95% confidence interval 1.10–1.72) to persons free from HTN. The incubation period from HTN to onset of CTN varied from 3 to 504 months in our study. HTN is associated with a higher risk of developing CTN and microcirculation disturbance might be the common underlying pathogenesis of the two diseases. More work should be done on this topic in the future to improve the etiological research in CTN and devise a new therapeutic modality.