Blood pressure and cognitive decline - the impact of hypertension over one decade.

BACKGROUND: Midlife hypertension is a risk factor for cognitive decline in late-life but little is known about the impact of long-term hypertension on cognitive change over time. METHODS: We examined blood pressure and cognitive function in 2777 participants (baseline: 2000-2003, 45-75 years, 48.4% men) from the Heinz Nixdorf Recall study. Blood pressure was assessed at three study visits and cognitive function was assessed at both follow-ups (mean follow-up: 5.1 years). Z-score differences in five neuropsychological tests, defining cognitive decline, were derived from linear regression models including age and education. The association of cognitive decline over 5 years and blood pressure over 10 years (classified as: normal blood pressure (>10 years, reference), prevalent hypertension (>10 years), incident hypertension t1 (>5 years), incident hypertension t2 (<5 years), temporary hypertension (at least one hypertensive reading)) was calculated using linear regression models resulting in coefficient b and 95% confidence interval. We calculated interactions with age (linear and with a cutoff at 65 years). RESULTS: Participants with prevalent hypertension showed a greater cognitive decline in both verbal memory tests. Incident hypertension t1 was associated with a greater decline in the visuospatial organization test. There was no interaction with age. CONCLUSION: This study showed that prevalent high blood pressure over 10 years is related to cognitive decline. Prevalent hypertension with longer exposure time may be more detrimental than temporary hypertension for cognitive function.

Subjective cognitive decline, APOE ε4, and incident mild cognitive impairment in men and women.

INTRODUCTION: Possible joint effects of subjective cognitive decline (SCD) and apolipoprotein E (APOE) ε4 genotype on incident mild cognitive impairment (MCI) were examined for men and women separately. METHODS: Cognitively normal participants with and without SCD were included from the first follow-up examination of the population-based Heinz Nixdorf Recall study. Sex-stratified logistic regression models estimated main effects and interactions (additive, multiplicative) of SCD at the first follow-up (yes+/no-) and APOE ε4 (positive+/negative-) groups for MCI 5 years later. RESULTS: Odds for MCI 5 years later were higher in SCD/APOE ε4 group +/+ than the sum of groups +/- and -/+ in women, with a trend for positive interaction. Odds for incident MCI in men was highest in group +/-, with no interaction effect. DISCUSSION: Our findings indicate that APOE ε4 may play an important role in the association of SCD and incident MCI, especially considering sex. Further studies need to examine these associations with larger sample sizes.

An increase of fractional exhaled nitric oxide after specific inhalation challenge is highly predictive of occupational asthma.

PURPOSE: An increase of fractional exhaled nitric oxide (FeNO) has been described after specific inhalation challenges (SICs) with occupational allergens, but the clinical role of FeNO measurements before and after SIC is unknown. It was the aim of this study to assess the diagnostic accuracy of FeNO measurements before and after SIC in subjects with suspected occupational asthma (OA). METHODS: One hundred forty-eight patients with suspected OA were examined by SIC with various occupational allergens. Subjects were assigned to pulmonary responders, nonresponders or doubtful by standard lung function criteria. FeNO was measured before SIC (baseline) and 24 h afterwards. Subjects with negative or doubtful SIC but increase of FeNO were evaluated individually by an overall expert rating. Effect modifiers of FeNO increases were assessed by regression analyses. RESULTS: Thirty-one patients (21%) were classified as pulmonary responders, 105 (71%) as nonresponders and 12 (8%) as doubtful. With the pulmonary responder status as gold standard an increase of FeNO ≥ 13 ppb showed a specificity of 0.9 and a sensitivity of 0.5. Seventeen subjects with negative or doubtful responder status showed such an increase of FeNO, among them 13 subjects with definitive or probable OA after expert rating. Regression analyses revealed no significant modifiers for the FeNO increase. CONCLUSION: An increase of FeNO after SIC is highly predictive of OA and should be regarded as an additional criterion for the interpretation of SIC with occupational agents.

Association of exposure to manganese and iron with relaxation rates R1 and R2*- magnetic resonance imaging results from the WELDOX II study.

OBJECTIVE: Magnetic resonance imaging is a non-invasive method that allows the indirect quantification of manganese (Mn) and iron (Fe) accumulation in the brain due to their paramagnetic features. The WELDOX II study aimed to explore the influence of airborne and systemic exposure to Mn and Fe on the brain deposition using the relaxation rates R1 and R2* as biomarkers of metal accumulation in regions of interest in 161 men, including active and former welders. MATERIAL AND METHODS: We obtained data on the relaxation rates R1 and R2* in regions that included structures within the globus pallidus (GP), substantia nigra (SN), and white matter of the frontal lobe (FL) of both hemispheres, as well as Mn in whole blood (MnB), and serum ferritin (SF). The study subjects, all male, included 48 active and 20 former welders, 41 patients with Parkinson's disease (PD), 13 patients with hemochromatosis (HC), and 39 controls. Respirable Mn and Fe were measured during a working shift for welders. Mixed regression models were applied to estimate the effects of MnB and SF on R1 and R2*. Furthermore, we estimated the influence of airborne Mn and Fe on the relaxation rates in active welders. RESULTS: MnB and SF were significant predictors of R1 but not of R2* in the GP, and were marginally associated with R1 in the SN (SF) and FL (MnB). Being a welder or suffering from PD or HC elicited no additional group effect on R1 or R2* beyond the effects of MnB and SF. In active welders, shift concentrations of respirable Mn>100µg/m3 were associated with stronger R1 signals in the GP. In addition to the effects of MnB and SF, the welding technique had no further influence on R1. CONCLUSIONS: MnB and SF were significant predictors of R1 but not of R2*, indicative of metal accumulation, especially in the GP. Also, high airborne Mn concentration was associated with higher R1 signals in this brain region. The negative results obtained for being a welder or for the techniques with higher exposure to ultrafine particles when the blood-borne concentration was included into the models indicate that airborne exposure to Mn may act mainly through MnB.