RESUMO
Identifying promoters of cerebral small vein integrity is important to counter vascular contributions to cognitive impairment and dementia. PURPOSE: In this preliminary investigation, the effects of a randomized 24-month physical activity (PA) intervention on changes in cerebral small vein integrity were compared to those of a health education (HE) control. METHODS: Cerebral small vein integrity was measured in 24 older adults (n = 8, PA; n = 16, HE) using ultra-high field MRI before and at the end of the 24-month intervention. Deep medullary veins were defined as straight or tortuous; percent change in straight length, tortuous length, and tortuosity ratio were computed. Microbleed count and white matter hyperintensities were also rated. RESULTS: Accelerometry-based values of PA increased by 17.2% in the PA group but declined by 28.0% in the HE group. The PA group, but not the HE group, had a significant increase in straight vein length from baseline to 24-month follow-up (P = 0.02 and P = 0.21, respectively); the between-group difference in percent change in straight length was significant (increase: median, 93.6%; interquartile range, 112.9 for PA; median, 28.4%; interquartile range, 90.6 for HE; P = 0.07). Between group differences in other markers were nonsignificant. CONCLUSIONS: Increasing PA in late-life may promote cerebral small vein integrity. This should be confirmed in larger studies.
Assuntos
Veias Cerebrais/fisiologia , Exercício Físico/fisiologia , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/fisiopatologia , Veias Cerebrais/diagnóstico por imagem , Veias Cerebrais/patologia , Circulação Cerebrovascular , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/prevenção & controle , Demência/patologia , Demência/fisiopatologia , Demência/prevenção & controle , Feminino , Educação em Saúde , Humanos , Angiografia por Ressonância Magnética , Masculino , Substância Branca/irrigação sanguínea , Substância Branca/diagnóstico por imagemRESUMO
OBJECTIVE: To examine the cross-sectional association between physical activity (PA) and hippocampal volume in middle-aged adults with childhood-onset type 1 diabetes (T1D), and whether hyperglycemia and insulin sensitivity contribute to this relationship. METHODS: We analyzed neuroimaging and self-reported PA data from 79 adults with T1D from the Pittsburgh Epidemiology of Diabetes Complications Study (mean age 50 years, mean duration 41 years) and 122 similarly aged adults without T1D (mean age 48 years). Linear regression models, controlling for intracranial volume, sex, education, and age, tested associations between PA and gray matter volumes of hippocampi and total brain in the 2 groups. For the T1D group, models further controlled for hyperglycemia and glucose disposal rate, a measure of insulin sensitivity. RESULTS: PA was significantly lower in the T1D than in the non-T1D group (median [interquartile range] 952 kcal [420-2,044] vs 1,614 kcal [588-3,091], respectively). Higher PA was significantly associated with larger hippocampi for T1D, but not for non-T1D (standardized ß [p values] from regression models adjusted for intracranial volume, sex, age, and education: 0.270 [p < 0.001] and 0.098 [p = 0.12], respectively). Neither hyperglycemia nor glucose disposal rate substantially modified this association. Relationships between PA and total brain gray matter volume were similar. CONCLUSIONS: A cross-sectional association between higher PA and larger hippocampi is already detectable by middle age for these patients with T1D, and it appears robust to chronic hyperglycemia and insulin sensitivity. Proof-of-concept studies should investigate whether increasing PA preserves hippocampal volume and the mechanisms underlying the effects of PA on hippocampal volume.
Assuntos
Diabetes Mellitus Tipo 1/diagnóstico por imagem , Diabetes Mellitus Tipo 1/fisiopatologia , Exercício Físico , Hipocampo/diagnóstico por imagem , Estudos Transversais , Exercício Físico/fisiologia , Feminino , Seguimentos , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , AutorrelatoRESUMO
OBJECTIVE: Psychomotor slowing is a common cognitive complication in type 1 diabetes (T1D), but its neuroanatomical correlates and risk factors are unclear. In nondiabetic adults, smaller gray matter volume (GMV) and presence of white matter hyperintensities are associated with psychomotor slowing. We hypothesize that smaller GMV in prefronto-parietal regions explains T1D-related psychomotor slowing. We also inspect the contribution of microvascular disease and hyperglycemia. METHODS: GMV, white matter hyperintensities (WMH), and glucose levels were measured concurrently with a test of psychomotor speed (Digit Symbol Substitution Test [DSST]) in 95 adults with childhood-onset T1D (mean age/duration = 49/41 years) and 135 similarly aged non-T1D adults. Linear regression models tested associations between DSST and regional GMV, controlling for T1D, sex, and education; a bootstrapping method tested whether regional GMV explained between-group differences in DSST. For the T1D cohort, voxel-based and a priori regions-of-interest methods further tested associations between GMV and DSST, adjusting for WMH, hyperglycemia, and age. RESULTS: Bilateral putamen, but no other regions examined, significantly attenuated DSST differences between the cohorts (bootstrapped unstandardized indirect effects: -3.49, -3.26; 95% confidence interval = -5.49 to -1.80, -5.29 to -1.44, left and right putamen, respectively). Among T1D, DSST was positively associated with GMV of bilateral putamen and left thalamus. Neither WMH, hyperglycemia, age, nor other factors substantially modified these relationships. CONCLUSIONS: For middle-aged adults with T1D and cerebral microvascular disease, GMV of basal ganglia may play a critical role in regulating psychomotor speed, as measured via DSST. Studies to quantify the impact of basal ganglia atrophy concurrent with WMH progression on psychomotor slowing are warranted.
Assuntos
Gânglios da Base/patologia , Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Diabetes Mellitus Tipo 1/complicações , Substância Cinzenta/patologia , Desempenho Psicomotor/fisiologia , Adulto , Gânglios da Base/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/etiologia , Doenças de Pequenos Vasos Cerebrais/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Estudos de Coortes , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The aim of this study was to investigate the presence and correlates of clinically relevant cognitive impairment in middle-aged adults with childhood-onset type 1 diabetes (T1D). RESEARCH DESIGN AND METHODS: During 2010-2013, 97 adults diagnosed with T1D and aged <18 years (age and duration 49 ± 7 and 41 ± 6 years, respectively; 51% female) and 138 similarly aged adults without T1D (age 49 ± 7 years; 55% female) completed extensive neuropsychological testing. Biomedical data on participants with T1D were collected periodically since 1986-1988. Cognitive impairment status was based on the number of test scores ≥1.5 SD worse than demographically appropriate published norms: none, mild (only one test), or clinically relevant (two or more tests). RESULTS: The prevalence of clinically relevant cognitive impairment was five times higher among participants with than without T1D (28% vs. 5%; P < 0.0001), independent of education, age, or blood pressure. Effect sizes were large (Cohen d 0.6-0.9; P < 0.0001) for psychomotor speed and visuoconstruction tasks and were modest (d 0.3-0.6; P < 0.05) for measures of executive function. Among participants with T1D, prevalent cognitive impairment was related to 14-year average A1c >7.5% (58 mmol/mol) (odds ratio [OR] 3.0; P = 0.009), proliferative retinopathy (OR 2.8; P = 0.01), and distal symmetric polyneuropathy (OR 2.6; P = 0.03) measured 5 years earlier; higher BMI (OR 1.1; P = 0.03); and ankle-brachial index ≥1.3 (OR 4.2; P = 0.01) measured 20 years earlier, independent of education. CONCLUSIONS: Clinically relevant cognitive impairment is highly prevalent among these middle-aged adults with childhood-onset T1D. In this aging cohort, chronic hyperglycemia and prevalent microvascular disease were associated with cognitive impairment, relationships shown previously in younger populations with T1D. Two additional potentially modifiable risk factors for T1D-related cognitive impairment, vascular health and BMI, deserve further study.
Assuntos
Transtornos Cognitivos/etiologia , Diabetes Mellitus Tipo 1/complicações , Índice de Gravidade de Doença , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Cognição , Transtornos Cognitivos/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Razão de Chances , Fatores de RiscoRESUMO
Although the haptoglobin (Hp) 1-1 genotype is associated with a lower coronary artery disease (CAD) risk in diabetes, we recently reported an increased stroke incidence in type 1 diabetes with Hp 1-1. We, thus, evaluated differences in earlier brain vascular abnormality markers by Hp using neuroimaging. Neuroimaging was completed in 94 participants of the Pittsburgh Epidemiology of Diabetes Complications study with Hp genotyping available (mean age, 49; duration, 41 years). White matter hyperintensities (WMH) volume, lacunar infarcts, and gray matter atrophy were quantified. Sixteen percent were homozygous for Hp 1 and 43% for Hp 2. A significant trend toward increased WMH was observed with greater duration and the number of Hp 1 alleles. Associations were strongest for the interhemispheric connecting fibers of the corpus callosum. Allowing for duration, sex, waist-to-hip ratio, HbA1c, systolic blood pressure, and lipids in models with backward elimination, results were similar. No significant differences by Hp were noted for atrophy or lacunar infarcts. Consistent with its direct association with stroke, the Hp 1-1 genotype is associated with higher WMH in this population. Further, including mechanistic, studies on the role of the Hp genotype in cerebrovascular disease and the implications for worsening cognitive function are needed.