Protective Effect of Long-Term CPAP Therapy on Cognitive Performance in Elderly Patients with Severe OSA: The PROOF Study

OBJECTIVE

Obstructive sleep apnea syndrome (OSA) leads to a deterioration in cognitive functions, with regard to memory and executive functions. However, few studies have investigated the impact of treatment on these cognitive functions in elderly subjects.

METHODS

The study was conducted in a large cohort of subjects aged 65 years or older (the PROOF cohort). Subjects were not diagnosed or treated for OSA. Subjects underwent a polygraphic recording. Cognitive performance was assessed in all OSA subjects at baseline and 10 years later, whether or not they were receiving continuous positive airway pressure (CPAP) therapy.

RESULTS

A group of 126 patients were analyzed. Only 26% of them were treated, with therapy initiated at the discretion of the primary care physician. Among treated subjects, self-reported compliance with therapy was good (> 6 h/night on average), and 66% of them reported an improvement in their quality of life. Patients receiving CPAP treatment had a higher apneahypopnea index (p = 0.006), a higher oxygen desaturation index (p < 0.001), and experienced more pronounced daytime repercussions (p = 0.004). These patients showed a statistically significant improvement in mental agility (similarities test; p < 0.0001) and memory performance (Grober and Buschke delayed free recall; p = 0.02).

CONCLUSION

CPAP treatment is associated with the maintenance of memory performance over time.

Prevalence and determinants of subjective sleepiness in healthy elderly with unrecognized obstructive sleep apnea

OBJECTIVE

Obstructive sleep apnea (OSA) is associated with behavioral consequences such as excessive daytime sleepiness (EDS). The aim of this study was to establish the presence of sleepiness in elderly with unrecognized OSA and the factors explaining its occurrence.

METHODOLOGY

A total of 825 healthy elderly (aged ≥65 years) undergoing clinical, respiratory polygraphy, and heart-rate variability analysis were studied. According to the apnea-hypopnea index (AHI), the subjects were stratified in four categories: no-OSA (AHI <5), mild (5 > AHI <15), moderate (15 ≥ AHI <30), and severe OSA (AHI ≥30). Participants with EDS were defined on the basis of the Epworth Sleepiness Scale (ESS) score ≥10.

RESULTS

Overall, the mean ESS score was 5.7 ± 5.6, 14.9% showing EDS with an increasing trend according to OSA severity (p <0.001). Sleepy subjects were more frequently men, having a greater body mass index (BMI), alcohol intake, depression score, and indices of OSA severity (23% of severe OSA cases being sleepy). No differences were present between sleepy and non-sleepy subjects in regard to other clinical, metabolic, and autonomic nervous system measurements. Regression analyses adjusted for age, gender, BMI, hypertension, depression score, autonomic sleep fragmentation, and AHI and/or oxygen desaturation index revealed that gender (p <0.0001), depression score (p <0.0001), and BMI (p = 0.01) were the only significant factors affecting the presence of sleepiness in this population.

CONCLUSIONS

In healthy elderly with OSA, the prevalence of EDS was low, and it affected only severe cases. Despite a weak association between the ESS score and the AHI index, male gender and depression score were the most significant predictors for the occurrence of sleepiness.

Subjective sleep and cognitive complaints in 65 year old subjects: a significant association. The PROOF cohort

OBJECTIVE

The prevalence of subjective sleep and cognitive complaints increases with age. The purpose of this study was to investigate the link between subjective cognitive and sleep complaints in a population aged 65.

DESIGN AND SETTING

analysis of a cohort of 1011 subjects aged 65 years old at time of inclusion.

METHODS

Older people underwent a cognitive tests battery and a nocturnal polygraphy recording. Subjective cognitive difficulties were scored on the McNair and Kahn Scale. Subjective sleep complaints were evaluated according to the St. Mary's Hospital Sleep Questionnaire and the Epworth Sleepiness Scale score.

RESULTS

In a 65 years old population, an association between subjective cognitive difficulties and poor sleep quality was observed. This remained significant after adjustment on gender, depression score, anxiety, educational level, medication intake, Apnea/Hypopnea index, Body Mass Index and Mini-Mental State Examination (OR = 2.1; p = 0.0002). Similar significant association was demonstrated between subjective cognitive difficulties and daytime sleepiness (OR = 2.6; p = 0.0007).

CONCLUSION

There was a significant association between subjective cognitive and sleep complaints, and daytime sleepiness in our population of older people.

Eight-year parallel change in baroreflex sensitivity and memory function in a sample of healthy older adults

OBJECTIVES

To examine whether changes in the cardiac autonomic nervous system (ANS) over time, as expressed by baroreflex sensitivity (BRS), were associated with long-term changes in cognitive performance in elderly individuals without dementia.

DESIGN

Community-based 8-year longitudinal study.

SETTING

Clinical settings.

PARTICIPANTS

Individuals aged 66.9 ± 0.9 (N = 425).

MEASUREMENTS

At baseline and follow-up, subjects underwent a clinical interview, autonomic and vascular measurements, and a neuropsychological evaluation including attentional, executive, and memory tests using standardized Z-scores. BRS was defined as being normal, moderate, or severe alteration at each evaluation. On the basis of the longitudinal changes subjects were stratified as being stable, moderate or improved.

RESULTS

Mean attentional, executive, and memory change Z-scores were -0.41 ± 0.9, -0.15 ± 0.7, and -0.14 ± 0.8, respectively. BRS of 56% of the subjects remained unchanged, of 20% decreased, and of 24% improved. After regression analysis, the worsened BRS group was 1.88 times as likely to have greater memory change as the group with stable BRS (P = .02). No significant association was found between longitudinal change in BRS and attentional and executive changes.

CONCLUSION

In healthy elderly individuals, BRS decrease was associated with a weak but significant decrease in memory function. The long-term effect of BRS on memory changes may suggest a role of the ANS in cognitive decline.

Sleep breathing disorders and cognitive function in the elderly: an 8-year follow-up study. the proof-synapse cohort

STUDY OBJECTIVES

Sleep breathing disorder (SBD) may be an important factor in age-related cognitive decline. In a cohort of healthy elderly subjects, we performed an 8-y longitudinal study to assess whether changes in cognitive function occur in untreated elderly patients with SBD and without dementia and the factors implicated in these changes.

DESIGN

A population-based longitudinal study.

SETTING

Clinical research settings.

PARTICIPANTS

A total of 559 participants of the PROOF study aged 67 y at the study entry and free from neurological disorders were examined.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Abnormal breathing events were defined by an apnea-hypopnea index (AHI) > 15. The raw cognitive data and averaged Z-scores for the attentional, executive, and memory functions were collected at the baseline and follow-up. At baseline, AHI > 15 was found in 54% of subjects with 18% having an AHI > 30. At follow-up, the presence of abnormal breathing events was associated with a slight but significant decline in the attentional domain (P = 0.01), which was more evident in the subjects with an AHI > 30 (P = 0.004). No significant changes over time were observed in the executive and memory functions. Several indices of chronic hypoxemia, defined either as a cumulative peripheral oxygen saturation (SpO2) < 90% or a minimal SpO2, accounted for portions of the variance in the decline in attention. All observed effects were small, accounting for 4-7% of variance in multivariate models.

CONCLUSION

In healthy elderly subjects, various components of sleep breathing disorder at baseline were associated with small changes in selected cognitive functions specific to the attention domain after controlling for multiple comorbidities, such as sleepiness, hypertension, diabetes, anxiety, and depression.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifiers NCT 00759304 and NCT 00766584.

Seven-year predictors of self-rated health and life satisfaction in the elderly: the PROOF study

OBJECTIVES

To investigate the relationship between cognitive performance, affective state, metabolic syndrome and 7-year follow-up self-rated health (SRH) and perceived life satisfaction (PLS).

DESIGN

Analysis of a prospective cohort study.

SETTING

The PROOF study, including 1011 elderly community residents.

PARTICIPANTS

Six hundred and fifty seven subjects completed metabolic syndrome (Met S) variables, neuropsychological and affective measurements at baseline, and then returned a 7-year follow-up questionnaire which included SRH and PLS.

MEASUREMENTS

The prospective association between cognitive function, Met S and each of its components, and affective disorders and subsequent subjective health and quality of life was examined. Covariates included educational level and use of tobacco. The analyses were made in men and women separately.

RESULTS

In multivariate models, the presence of Met S was significantly associated to weaker SRH (OR = 2.78, p = 0.009 in men and OR = 2.0, p = 0.02 in women). Higher triglycerides rate were associated with weaker SRH in men (OR = 2.23, p = 0.002) and higher fasting glucose in women (OR = 2.54, p = 0.006). Global Met S and abdominal obesity was significantly associated to weaker PLS in women only (respectively OR = 2.70, p = 0.0002 and OR = 1.9, p = 0.02). Depressive symptoms were significantly associated to both weaker SRH and PLS in men (OR = 1.30, p = 0.002; OR = 1.44, p < 0.0001 for SRH and PLS respectively) and in woman (OR = 1.09, p = 0.04; OR = 1.26, p < 0.0001 for SRH and PLS respectively). Anxiety was linked to both weaker SRH and PLS in women (OR = 1.17, p = 0.002 and 0R = 1.11, p = 0.03 for SRH and PLS respectively). Finally, lower executive function was associated with weaker PLS in men (OR = 0.43, p = 0.0005).

CONCLUSION

metabolic syndrome and certain of its components, anxiety and depressive symptoms, are independent predictors of poorer subjective health and quality of life as assessed over a period of 7 years in a population of a non-demented aging community. Moreover, executive performance was linked to subsequent quality of life in men. Many of these factors being treatable, our findings point to the necessity of providing preventive care strategies by the management of cardiovascular risk factors and anxio-depressive symptoms.

Metabolic syndrome is associated with poor memory and executive performance in elderly community residents: the PROOF study

OBJECTIVE

Aging is associated with a loss of cognitive performance and an increasing occurrence of cardiovascular events. Moreover, cardiovascular risk factors are linked to cognitive impairment and dementia. Whereas individual components of metabolic syndrome (Met S) have been reported to be linked to cognitive decline and dementia, there are very few studies on Met S as a whole. The present study aims to assess the relationship between Met S and its components and cognitive functioning in a cohort of elderly non-demented community residents.

DESIGN

Population-based cohort study (PROOF study). Cross-sectional analysis.

PARTICIPANTS

Dementia-free community-dwellers aged 65.

MEASURES

The PROOF participants underwent an extensive neuropsychological battery at baseline. Summary cognitive measures including memory, attention, and executive performance were created by converting the individual test results to Z scores and computing the average scores within each domain. Each of the three cognitive scores was individually compared between groups as a function of Met S. The cognitive scores and the covariates which were significant in univariate analyses were then included in logistic regression models.

RESULTS

A significant association was observed between the presence of metabolic syndrome, poor memory, and executive function even after adjusting for confounding factors (memory: odds ratio: 1.77, p = 0.008; executive functions: odds ratio: 1.91, p = 0.002).

CONCLUSIONS

Our study showed that in a sample of elderly community dwellers, Met S was associated with poor memory and executive performance. These results underline the importance of detecting and managing metabolic syndrome components to prevent cognitive impairment and dementia.

Association of self-reported sleep and hypertension in non-insomniac elderly subjects

OBJECTIVES

Sleep duration and sleep quality play important roles in the development of hypertension (HT) in middle-aged subjects, with controversial data in elderly. In this study, we investigated the link between HT and self-reported sleep in non-insomniac elderly subjects.

METHODS

We examined 500 participants without insomnia complaints aged 72 ± 1 years. An extensive instrumental evaluation was carried out, including 24-h blood pressure (BP) monitoring and an assessment of nocturnal BP dipping. Sleep duration and quality were evaluated by the Pittsburgh Sleep Quality Index (PSQI). The subjects were stratified into three groups according to sleep duration: short (< 6 h), normal (> 6h to < 8 h), and long (> 8 h) sleepers. A PSQI < 5 defined good sleepers (GS, n = 252), and a PSQI > 5 (n = 248) defined poor sleepers (PS).

RESULTS

PS represented 50% of the subjects, more frequently females. Compared to GS, PS did not differ in terms of HT, BP, baroreflex sensitivity (BRS), and BP dipping. Short, normal, and long sleepers accounted for 28%, 42%, and 30% of subjects, with HT, BP values, BRS, and gender not differing between groups. No relationship was found between nocturnal BP values and self-reported sleep measures. Logistic regression analysis indicated that neither sleep duration nor sleep quality predicts the prevalence of HT, the body mass index being the only factor affecting this association.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifiers NCT00759304 and NCT00766584.

CONCLUSIONS

In a sample of non-insomniac elderly subjects, neither sleep duration nor sleep quality affected the prevalence of HT. These data argue against a relationship between self-reported sleep duration and quality and HT in elderly without insomnia.

Sleep-related autonomic overactivity in a general elderly population and its relationship to cardiovascular regulation

Alteration in cardiac autonomic activity during sleep is a common feature of sleep disorders. Diurnal sympathetic overactivity is a possible consequence and could contribute to future cardiovascular complications. The aim of this study is to assess the relationship between cardiac autonomic activity during sleep and diurnal autonomic cardiovascular control. In a large cohort (n = 1011) of subjects aged 65 years old (± 0.4) free of cardiac and cerebrovascular events and of sleep-related breathing disorders, we evaluated (cross-sectional study) the prevalence of unexpected alteration in sleep-related autonomic overactivity according to the presence of a cyclical nocturnal heart rate variability [quantified using the relative power spectral density of the very low-frequency band of the heart rate increment (VLFi%) from ECG Holter monitoring]. We tested its relationship with diurnal ambulatory blood pressure and spontaneous baroreflex sensitivity (sBRS). An abnormal cardiac autonomic activity during sleep was retained in 34.4% of this population according to a VLFi% >4. Using multiple logistic regression analysis, the severity of the autonomic alteration was mainly correlated after adjustment with lower sBRS (p = 0.01; OR: 0.94; 95% CI: 0.90-0.98). Diurnal baroreflex control alteration is associated with sleep-related autonomic overactivity elderly. Such alteration may contribute to the increased incidence of cardiovascular complications in sleep disorders.

Sleep-related breathing disorders and gait variability: a cross-sectional preliminary study

Background

Sleep-related breathing disorders (SRBDs) provoke cognitive and structural brain disorders. Because these disorders have been associated with unsafe gait characterized by an increase in stride-to-stride variability of stride time (STV), we hypothesised that SRBDs could be associated with an increased STV. The aim of this study was to examine the association between SRBDs and STV in French healthy older community-dwellers.

Methods

A total of 49 participants (mean age 69.6 ± 0.8years; 65.2% female) were included in this cross-sectional study. All participants, who were free of clinically diagnosed SRBDs before their inclusion, had a nocturnal unattended home-sleep assessment. There were separated in three group based on apnea + hypopnea index (AHI): AHI <15 defining the absence of SRBD, AHI between 15–30 defining mild SRBD, and AHI >30 defining moderate-to-severe SRBD. Coefficient of variation of stride time, which is a measure of STV, was recorded while usual walking using SMTEC® footswitches system. Digit span score was used as a measure of executive performance. Age, gender, body mass index (BMI), number of drugs daily taken, vision, proprioception, history of falls, depression symptoms, global cognitive functioning were also recorded.

Results

STV and BMI were higher in participants with mild SRBDs (P = 0.031 and P = 0.020) and moderate-to-severe SRBDs (P = 0.004 and P = 0.002) compared to non-SRBDs. STV positively correlated with AHI (P = 0.036). Lower (i.e., better) STV was associated with the absence of SRBDs (P = 0.021), while greater (i.e., worse) STV was associated with moderate-to-severe SRBD (P < 0.045) but not with mild SRBD (P > 0.06).

Conclusion

Our results show a positive association between STV and SRBDs, with moderate-to-severe SRBD being associated with greater gait variability. This association opens new perspectives for understanding gait disorders in older adults with SRBDs and opens the door to treatments options since SRBDs are potential treatable factors.

Skeletal muscle lipid content and oxidative activity in relation to muscle fiber type in aging and metabolic syndrome

One of the most noticeable effects of aging is the reduction in skeletal muscle mass and strength (sarcopenia). The metabolic syndrome (MS) is also prevalent in old subjects, but its relevance to skeletal muscle characteristics has poorly been investigated. Immunohistochemical studies were performed with muscle biopsies from young (22 years) and old (73 years) men with and without MS to reveal age-dependent and MS-associated modifications of fiber-type characteristics. Atrophy of type II fibers and altered fiber shape characterized muscle aging in lean healthy men. In contrast, increased cross-sectional area of the most abundant type I and type IIA fibers, and reduced cytochrome c oxidase content in all fiber types, characterized MS. Aging and particularly MS were associated with accumulation of intramyocellular lipid droplets. Although lipids mostly accumulated in type I fibers, matrix-assisted laser desorption/ionization-mass spectrometry imaging of intramyocellular lipids did not distinguish fiber types, but clearly separated young, old, and MS subjects. In conclusion, our study suggests that MS in the elderly persons is associated with alterations in skeletal muscle at a fiber-type specific level. Overall, these fiber type-specific modifications may be important both for the age-related loss of muscle mass and strength and for the increased prevalence of MS in elderly subjects.

Cardiac sympathetic modulation in response to apneas/hypopneas through heart rate variability analysis

Autonomic dysfunction is recognized to contribute to cardiovascular consequences in obstructive sleep apnea/hypopnea syndrome (OSAHS) patients who present predominant cardiovascular sympathetic activity that persists during wakefulness. Here, we examined 1) the factors that influence sympathetic cardiac modulation in response to apneas/hypopneas; and 2) the influence of autonomic activity during apneas/hypopneas on CA. Sixteen OSAHS patients underwent in-hospital polysomnography. RR interval (RR) and RR spectral analysis using wavelet transform were used to study parasympathetic (high frequency power: HF(WV)) and sympathetic (low frequency power: LF(WV) and LF(WV)/HF(WV) ratio) activity before and after apnea/hypopnea termination. Autonomic cardiac modulations were compared according to sleep stage, apnea/hypopnea type and duration, arterial oxygen saturation, and presence of CA. At apnea/hypopnea termination, RR decreased (p<0.001) while LF(WV) (p = 0.001) and LF(WV)/HF(WV) ratio (p = 0.001) increased. Only RR and LF(WV)/HF(WV) ratio changes were higher when apneas/hypopneas produced CA (p = 0.030 and p = 0.035, respectively) or deep hypoxia (p = 0.023 and p = 0.046, respectively). Multivariate statistical analysis showed that elevated LF(WV) (p = 0.006) and LF(WV)/HF(WV) ratio (p = 0.029) during apneas/hypopneas were independently related to higher CA occurrence. Both the arousal and hypoxia processes may contribute to sympathetic cardiovascular overactivity by recurrent cardiac sympathetic modulation in response to apneas/hypopneas. Sympathetic overactivity also may play an important role in the acute central response to apneas/hypopneas, and in the sleep fragmentation.

[Autonomic regulation and bradycardia during the neonatal period]

The high frequency of bradycardia observed during the neonatal period requires cardiac monitoring but also understanding its intrinsic mechanisms, including responsiveness of the autonomic nervous system (ANS). Heart rate variability and spontaneous baroreflex analysis can help understand the autonomic dysregulation of cardiorespiratory control, possibly responsible for sudden infant death. In clinical neonatology practice, neonatal bradycardia does not warrant continuation of monitoring if it remains isolated, asymptomatic, and short (<10 s), followed by a rapid cardiac acceleration indicating an adapted sympathetic response. Further evaluation of ANS responsiveness is possible for newborns including analyzing the complexity of the heart rate and respiratory variability. This allows better targeting children with high risk after discharge. The real-time evaluation of autonomic regulation could become a valuable tool in clinical practice.

Baroreflex sensitivity, vascular risk factors, and cognitive function in a healthy elderly population: the PROOF cohort

OBJECTIVES

To assess the role of the cardiac autonomic nervous system (ANS), as measured according to spontaneous cardiac baroreflex sensitivity (BRS), in the type and degree of cognitive performance in healthy young-elderly individuals, taking into account the presence of other vascular risk factors.

DESIGN

Community-based cross-sectional study.

SETTING

In-home and clinical settings.

PARTICIPANTS

A subset of participants, aged 66.9±0.9, from a prospective study that aimed to assess the influence of ANS activity on cardiovascular and cerebrovascular morbidity and mortality (N=916).

MEASUREMENTS

All subjects underwent a clinical interview, neuropsychological testing, and autonomic and vascular measurements. Three cognitive domains were defined: attentional (Trail-Making Test Part A, Stroop code and parts I & II), executive (Trail-Making Test Part B, Stroop part III, verbal fluency and similarity tests), and memory (Benton visual retention test, Grober and Buschké procedure). Subjects were stratified according to their scores into normal, low, and impaired performers.

RESULTS

After adjustments to demographic and vascular data, participants with moderate autonomic dysregulation (3<BRS≤6) were determined to be 1.82 times as likely to have memory impairment (odds ratio (OR)=1.82, 95% confidence interval (CI)=1.13-3.17, P=.02) and those with severe autonomic dysregulation (BRS≤3) to be 2.65 as likely (OR=2.65, 95% CI=1.40-5.59, P=.006) as participants with normal BRS (>6).

CONCLUSION

In older individuals without dementia, autonomic dysregulation seems to have a direct, gradual, and independent effect on memory. Future studies are needed to evaluate the long-term effects of BRS and other markers of the ANS on cognitive decline.

Obstructive sleep apnea is associated with preserved bone mineral density in healthy elderly subjects

STUDY OBJECTIVES

Chronic intermittent hypoxia (IH) acts as a stimulator of mesenchymal stem cell (MSC) mobilization, intensifying osteoblast formation in animal models. The recurrence of apnea and oxygen desaturation in obstructive sleep apnea (OSA) may mimic experimental models of IH. We hypothesized that in elderly with OSA, apnea-related IH may mobilize MSCs and thereby prevent the age-related decline in osteogenesis. This study explored the relationship between OSA and bone mineral density (BMD), and the effect of IH on BMD, in a large sample of elderly subjects.

PARTICIPANTS

There were 833 volunteers age 68.6 ± 0.8 y (59% women).

INTERVENTION

Each participant underwent evaluation of BMD at lumbar spine and femoral sites by dual-energy x-ray absorptiometry (DEXA) as well as clinical and polygraphic examinations. OSA was diagnosed on the basis of an apnea-hypopnea index (AHI) ≥ 15.

MEASUREMENTS AND RESULTS

There were 55% of the participants who presented with OSA, and these subjects were predominantly male and overweight. Compared with subjects without OSA, those with OSA had a higher femoral and spinal BMD (P < 0.001). Body mass index (BMI), AHI, and oxygen desaturation index (ODI) (P < 0.01) were significantly related to BMD. After adjustment for sex, BMI, metabolic values, and hypertension, multiple regression analysis showed a significant association between femoral and lumbar T scores and both daily energy expenditure (P < 0.001) and ODI (P = 0.007).

CONCLUSIONS

In elderly subjects, the presence of obstructive sleep apnea is associated with higher bone mineral density, with oxygen desaturation index being a significant determinant of bone metabolism. These results suggest that apnea-related intermittent hypoxia may stimulate the bone remodeling process in older population.

CLINICAL TRIAL REGISTRATION

NCT 00759304 and NCT 00766584.

Impaired baroreflex sensitivity and the risks of new-onset ambulatory hypertension, in an elderly population-based study

BACKGROUND

Impairment of the autonomic nervous system activity may be involved in the development of hypertension. Yet the prognostic values of heart rate variability and baroreflex sensitivity in the risk of new-onset ambulatory hypertension have not been investigated. We sought to assess the relationship between heart rate variability and baroreflex sensitivity parameters and ambulatory hypertension in a community-dwelling elderly cohort.

METHODS

Normotensive subjects were selected from the PROOF study cohort, including 1011 subjects aged 65 years at baseline. The autonomic nervous system activity was assessed through 24-hour heart rate variability and 15-minute spontaneous baroreflex sensitivity at baseline. Incident hypertension was defined with the 24-hour, day-time and night-time ambulatory blood pressure measurements and antihypertensive treatment use, at two-years of follow-up.

RESULTS

At baseline, 13.7% of subjects developed day-time hypertension, 18.2% developed night-time hypertension and 13.6% developed 24-hour hypertension. Reduced baroreflex sensitivity at baseline was associated with onset of hypertension after adjustment for blood pressure level, C-reactive protein levels and depression score (OR = 0.45 [0.23-0.86]). Indices of heart rate variability were not associated with hypertension onset.

CONCLUSION

Baroreflex sensitivity may represent an intermediate goal for prevention of ambulatory hypertension at early stage.

Association between severe obstructive sleep apnea and incident arterial hypertension in the older people population

OBJECTIVES

The impact of sleep-related breathing disorders on the incidence of arterial hypertension (AHT) in the older adults is not well-established. The aim of our study was to test the link between severe obstructive sleep apnea (OSA) and the occurrence of hypertension in older subjects after 3 years.

METHODS

372 normotensive subjects with a mean age of 68.2 years were included in our longitudinal study. All participants had a ventilatory polygraphic recording and an ambulatory blood pressure (BP) monitoring at baseline and after 3 years. Severe OSA was defined by an apnea-hypopnea index (AHI) of ≥ P30 per hour. A new onset of hypertension was defined according to a mean 24-hour value >140mmHg for systolic BP and >85mmHg for diastolic BP or the use of antihypertensive medication.

RESULTS

The baseline factors significantly associated with an increased risk for new-onset hypertension were male gender, obesity, diabetes mellitus (DM), dyslipidemia, and OSA. Multiple logistic regression analyses showed that an AHI ≥30 per hour was independently associated with incident hypertension after 3 years (P=.02; odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1-2.8).

CONCLUSIONS

The presence of severe OSA is associated with new-onset AHT in normotensive elderly (mean age, 68.2 y) subjects.

Relation of central fat mass to obstructive sleep apnea in the elderly

STUDY OBJECTIVES

Obesity is a recognized risk factor for obstructive sleep apnea syndrome (OSAS). We evaluated whether total trunk and central fat mass (CFM) is associated with OSAS in elderly subjects.

DESIGN

Cross-sectional.

SETTING

Body composition assessment by dual-energy X-ray absorbsiometry (DEXA).

PARTICIPANTS

749 volunteers aged 67.2 ± 0.8 years (59.4% women).

INTERVENTION

All participants underwent evaluation of their body composition by DEXA in parallel with clinical and polygraphic assessments. The presence of OSAS was defined by an apnea plus hypopnea index (AHI) ≥ 15.

MEASUREMENTS AND RESULTS

A total of 44.8% of the population had an AHI < 15, and 55.2% presented OSAS. OSAS subjects were more frequently overweight and had a higher total trunk fat mass and central fat mass (CFM). Correlation analyses revealed that body mass index (r = 0.27, P < 0.001), neck circumference (r = 0.35, P < 0.001), and CFM (r = 0.23, P < 0.001) were significantly related to AHI. Logistic regression analysis indicated that in mild OSAS cases (> 15AHI < 30), BMI (OR: 1.10; 95% CI: 1.03-1.18; P = 0.008), and male gender (OR: 1.49; 95% CI: 1.05-2.12, P = 0.03) were key factors explaining an AHI between 15 and 30. In severe cases (AHI > 30), male gender (OR: 3.65; 95% CI: 2.40-5.55; P < 0.001) and CFM (OR: 1.10; 95% CI: 1.03-1.19; P = 0.009) were significant independent predictors of OSAS.

CLINICAL TRIAL REGISTRATION

NCT 00759304 and NCT 00766584.

CONCLUSIONS

Although central fat mass plays a role in the occurrence of severe OSAS in men older than 65 years of age, its low discriminative sensitivity in mild OSAS cases does not warrant systematic use of DEXA for the diagnosis of OSAS.

Depressive symptoms and autonomic nervous system dysfunction in an elderly population-based study: the PROOF study

BACKGROUND

To assess the relationship between depressive symptoms, evaluated through self-reported history as well as current depressive symptoms, and impaired autonomic nervous system activity, evaluated by long-term heart rate variability and baroreflex sensitivity among elderly community residents, aged 65 years.

METHODS

Subjects from the Proof cohort Study were evaluated for depressive symptoms and self-reported history of depression at inclusion. Autonomic nervous system activity was assessed through 24-h heart rate variability and baroreflex sensitivity. Cross-sectional analyses were performed to study the relationship between the different status of depression and autonomic nervous system activity.

RESULTS

Among the 1011 Proof study participants, 823 subjects were included in the analyses. Current depressive symptoms were present among 67 subjects; history of depression was reported by 228 subjects. Psychoactive drugs were used by 59 subjects. Low frequency (p=0.02), very low frequency (p<0.01) and Low/High frequency ratio (p<0.001) were lower among subjects with depressive symptoms and history of depression, independently of antidepressant treatment. The association remained significant for Low/High frequency ratio after adjustment for gender and physical activity (p=0.004).

CONCLUSION

Current depressive symptoms may be linked to autonomic nervous system lower performances. A possible long-term effect of depressive symptoms at middle-age may influence later-life autonomic nervous system activity. Our results highlight the importance of taking into account the depressive symptoms in the cardiovascular risk, even in the elderly.

Association between ambulatory 24-hour blood pressure levels and brain volume reduction: a cross-sectional elderly population-based study

Previous literature has shown mixed results regarding the association between blood pressure levels and brain volume reduction. The objectives of this study were to determine whether high blood pressure levels were associated with focal brain volume reduction and whether high blood pressure-related focal brain volume reduction was associated with a decline in executive function performance. On the basis of a cross-sectional design, 24-hour ambulatory blood pressure measurements, as well as brain morphology from 3-dimensional magnetic resonance images, were assessed among 183 participants (mean, 65 ± 0.6 years; 62.4% women). Average levels of systolic and diastolic blood pressures, as well as dip, pulse pressure, and mean arterial blood pressure, were used as outcomes. Cortical gray and white matter volumes were determined by automatic calculation using Statistical Parametric Mapping segmentation. Folstein's Mini-Mental State Examination, digit span, part B of Trail Making, and Stroop tests were used to assess executive function performance. Sex, use of antihypertensive drugs, duration of hypertension, leukoaraiosis, body mass index, education level, and total brain matter volume were used as potential confounders. A significant blood pressure-related decrease in gray matter volume of the left supplementary motor areas (Brodmann area 6) and of the left superior and middle frontal gyrus (Brodmann area 8) was shown. No significant decrease was found with white matter volume. Blood pressure-related decreases in gray matter volume were significantly associated with a decline in executive function performance. The association of high blood pressure with brain volume reduction may in part explain blood pressure-related cognitive decline leading to dementia.

Contribution of brain imaging to the understanding of gait disorders in Alzheimer's disease: a systematic review

Although gait disorders are common in Alzheimer's disease (AD), determining which brain structures and related lesions are specifically involved is a goal yet to be reached. Our objective was to systematically review all published data that examined associations between gait disorders and brain imaging in AD. Of 486 selected studies, 4 observational studies met the selection criteria. The number of participants ranged from 2 to 61 community dwellers (29%-100% female) with prodromal or dementia-stage AD. Quantitative gait disorders (ie, slower gait velocity explained by shorter stride length) were associated with white matter lesions, mainly in the medial frontal lobes and basal ganglia. The nigrostriatal dopamine system was unaffected. Qualitative gait disorders (ie, higher stride length variability) correlated with lower hippocampal volume and function. Gait disorders in AD could be explained by a high burden of age-related subcortical hyperintensities on the frontal-subcortical circuits (nonspecific) together with hippocampal atrophy and hypometabolism (specific).

Diabetes, impaired fasting glucose, and cognitive decline in a population of elderly community residents

BACKGROUND AND AIMS

Diabetes and impaired fasting glucose, as well as cognitive impairment, are common in the elderly. Although several cross-sectional studies have demonstrated the influence of diabetes on cognitive impairment, only a few longitudinal studies have assessed the relationship between diabetes, impaired fasting glucose and cognitive decline in non-demented elderly community dwellers, by means of extensive neuropsychological batteries. The present study assesses the relationship between baseline diabetes, impaired fasting glucose (IFG) and 2- year evolution of memory, attention and executive performance in a sample of non-demented elderly subjects.

METHODS

DESIGN

Population-based cohort study [(PROgnostic indicator OF cardiovascular and cerebrovascular events (PROOF)].

PARTICIPANTS

One hundred and sixty-three community dwellers aged 65 years without dementia at recruitment.

MAIN OUTCOME MEASURES

Memory, attention and executive performance.

RESULTS

A significant association was observed between baseline diabetes mellitus and a higher 2-year decline in the Trial Making Test B and Stroop test exploring attention and executive function. This effect remained significant after adjusting for age, gender, education, anxiety and depressive symptoms, as well as other cardiovascular risk factors (F=2.41; p=0.007). Instead, no relationship was observed between IFG and cognitive decline.

CONCLUSIONS

Our study showed that, in a sample of elderly non-demented community dwellers, diabetes mellitus (but not IFG) is associated with a higher decline in selective attention and executive functioning. These results emphasize the importance of detecting and man- aging diabetes and impaired fasting glucose, in order to prevent cognitive impairment and dementia.

Sleep apnea syndrome and cognition

Obstructive sleep apnea (OSA) is a sleep-related breathing disorder characterized by repetitive episodes of airflow cessation resulting in brief arousals and intermittent hypoxemia. Several studies have documented significant daytime cognitive and behavioral dysfunction that seems to extend beyond that associated with simple sleepiness and that persists in some patients after therapeutic intervention. A still unanswered question is whether cognitive symptoms in OSA are primarily a consequence of sleep fragmentation and hypoxemia, or whether they coexist independently from OSA. Moreover, very little is known about OSA effects on cognitive performances in the elderly in whom an increased prevalence of OSA is present. In this review we will consider recent reports in the association between sleep apnea and cognition, with specific interest in elderly subjects, in whom sleep disturbances and age-related cognitive decline naturally occur. This will allow us to elucidate the behavioral and cognitive functions in OSA patients and to gain insight into age differences in the cognitive impairment. Clinically, these outcomes will aid clinicians in the evaluation of diurnal consequences of OSA and the need to propose early treatment.

A 3-year longitudinal study of sleep disordered breathing in the elderly

Limited and controversial data exist on the natural evolution of sleep disordered breathing (SDB) in untreated individuals. This study examines the evolution of SDB over a 3-yr period in a community-based sample of elderly subjects. From the initial cohort of 854 healthy subjects aged mean ± SD 68.4 ± 0.8 yrs, 519 untreated subjects accepted clinical and instrumental follow-up 3.6 ± 1.6 yrs later. SDB was defined as a respiratory disturbance index (RDI) >15 events · h(-1). At baseline, 202 (39%) subjects had an RDI ≤ 15 events · h(-1) and 317 (61%) had an RDI >15 events · h(-1). 3 yrs later, 280 (54%) subjects were non-SDB and 239 (46%) had SDB. Between evaluations, the RDI decreased from 22.3 ± 16.2 to 16.4 ± 13.0 events · h(-1), with a greater decrease in the number of cases with an RDI >30 events · h(-1) that in those with RDI ≥ 30 events · h(-1). In the non-SDB group, 81% had a stable RDI and 19% increased their RDI by a mean of 13.7 events · h(-1). In the SDB group, the RDI decreased to values ≤ 15 events · h(-1) in 36.6% of cases, 63.4% still having SDB. The RDI changes did not depend on weight changes. In healthy elderly subjects, the prevalence and severity of SDB did not show a tendency toward natural worsening, some cases having improvement or a remission independent of weight changes. These findings also suggest that in the elderly, natural SDB progression is still hypothetical.

Healthcare-associated infection in Irish long-term care facilities: results from the First National Prevalence Study

BACKGROUND

Prevalence of healthcare-associated infection (HCAI) and antimicrobial use in Irish long-term care facilities (LTCFs) has never been studied.

AIM

To collect baseline data on HCAI prevalence and antibiotic use in Irish LTCFs to inform national LTCF policy and plan future HCAI prevention programmes.

METHODS

A prevalence study of HCAI and antibiotic use was undertaken in Irish LTCFs. Participation was voluntary. Data on HCAI risk factors, signs and symptoms of infection and antimicrobial use were collected prospectively on a single day in each institution.

FINDINGS

Sixty-nine Irish LTCFs participated and 4170 eligible residents were surveyed; 472 (11.3%) had signs/symptoms of infection (266, 6.4%) and/or were on antibiotics (426, 10.2%). A third of residents (1430, 34.3%) were aged ≥85 years and more than half disorientated (2110, 50.6%) with impaired mobility (2101, 50.4%). HCAI prevalence was 3.7% (range: 0-22.2%). The most common HCAI was urinary tract infection (UTI) (62 residents, 40% of HCAI). Presence of a urinary catheter was associated with UTI (P < 0.0000001). Antibiotics were prescribed for treatment (262 residents, 57.8%) and prophylaxis (182 residents, 40.2%) of infection. The most common indication for prophylaxis was UTI prevention (35.8% of total prescriptions). Fourteen (10.2%) residents on UTI prophylaxis had a urinary catheter. The most common indications for therapy included respiratory tract infections (35.1%), UTI (32.1%) and skin infection (21.8%).

CONCLUSION

This study highlights the frequency of prophylactic antimicrobial prescribing and provides an important baseline to inform future preventive strategies.