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1.
PLoS One ; 17(10): e0275169, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36215237

RESUMO

OBJECTIVES: Family caregivers play a fundamental role in the care of the older blunt trauma patient. We aim to identify risk factors for negative and positive experiences of caregiving among family caregivers. DESIGN: Prospective, nationwide, multi-center cohort study. SETTING AND PARTICIPANTS: 110 family caregivers of Singaporeans aged≥55 admitted for unintentional blunt trauma with an Injury Severity Score (ISS) or New Injury Severity Score (NISS)≥10 were assessed for caregiving-related negative (disturbed schedule and poor health, lack of family support, lack of finances) and positive (esteem) experiences using the modified-Caregiver Reaction Assessment (m-CRA) three months post-injury. METHODS: The association between caregiver and patient factors, and the four m-CRA domains were evaluated via linear regression. RESULTS: Caregivers of retired patients and caregivers of functionally dependent patients (post-injury Barthel score <80) reported a worse experience in terms of disturbed schedule and poor health (ß-coefficient 0.42 [95% Confidence Interval 0.10, 0.75], p = .01; 0.77 [0.33, 1.21], p = .001), while male caregivers and caregivers who had more people in the household reported a better experience (-0.39 [-0.73, -0.06], p = .02; -0.16 [-0.25, -0.07], p = .001). Caregivers of male patients, retired patients, and patients living in lower socioeconomic housing were more likely to experience lack of family support (0.28, [0.03, -0.53], p = .03; 0.26, [0.01, 0.52], p = .05; 0.34, [0.05, -0.66], p = .02). In the context of lack of finances, caregivers of male patients and caregivers of functionally dependent patients reported higher financial strain (0.74 [0.31, 1.17], p = .001; 0.84 [0.26, 1.43], p = .01). Finally, caregivers of male patients reported higher caregiver esteem (0.36 [0.15, 0.57], p = .001). CONCLUSIONS AND IMPLICATIONS: Negative and positive experiences of caregiving among caregivers of older blunt trauma patients are associated with pre-injury disability and certain patient and caregiver demographics. These factors should be considered when planning the post-discharge support of older blunt trauma patients.


Assuntos
Cuidadores , Ferimentos não Penetrantes , Assistência ao Convalescente , Estudos de Coortes , Família , Humanos , Masculino , Alta do Paciente , Estudos Prospectivos , Inquéritos e Questionários
2.
J Am Med Dir Assoc ; 23(4): 646-653.e1, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34848197

RESUMO

OBJECTIVE: Frailty is associated with morbidity and mortality in older injured patients. However, for older blunt-trauma patients, increased frailty may not manifest in longer length of stay at index admission. We hypothesized that owing to time spent in hospital from readmissions, frailty would be associated with less total time at home in the 1-year postinjury period. DESIGN: Prospective, nationwide, multicenter cohort study. SETTING AND PARTICIPANTS: All Singaporean residents aged ≥55 years admitted for blunt trauma with an Injury Severity Score (ISS) or New Injury Severity Score (NISS) ≥10 from March 2016 to July 2018. METHODS: Frailty (by modified Fried criteria) was assessed at index admission, based on questions on preinjury weight loss, slowness, exhaustion, physical activity, and grip strength at the time of recruitment. Low time at home was defined as >14 hospitalized days within 1 year postinjury. The contribution of planned and unplanned readmission to time at home postinjury was explored. Functional trajectory (by Barthel Index) over 1 year was compared by frailty. RESULTS: Of the 218 patients recruited, 125 (57.3%) were male, median age was 72 years, and 48 (22.0%) were frail. On univariate analysis, frailty [relative to nonfrail: odds ratio (OR) 3.45, 95% confidence interval (CI) 1.33-8.97, P = .01] was associated with low time at home. On multivariable analysis, after inclusion of age, gender, ISS, intensive care unit admission, and surgery at index admission, frailty (OR 5.21, 95% CI 1.77-15.34, P < .01) remained significantly associated with low time at home in the 1-year postinjury period. Unplanned readmissions were the main reason for frail participants having low time at home. Frail participants had poorer function in the 1-year postinjury period. CONCLUSIONS AND IMPLICATIONS: In the year following blunt trauma, frail older patients experience lower time at home compared to patients who were not frail at baseline. Screening for frailty should be considered in all older blunt-trauma patients, with a view to being prioritized for postdischarge support.


Assuntos
Assistência ao Convalescente , Ferimentos não Penetrantes , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Idoso Fragilizado , Avaliação Geriátrica , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Estudos Prospectivos
3.
PLoS One ; 16(4): e0250803, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33930058

RESUMO

BACKGROUND: Patients suffering moderate or severe injury after low falls have higher readmission and long-term mortality rates compared to patients injured by high-velocity mechanisms such as motor vehicle accidents. We hypothesize that this is due to higher pre-injury frailty in low-fall patients, and present baseline patient and frailty demographics of a prospective cohort of moderate and severely injured older patients. Our second hypothesis was that frailty was associated with longer length of stay (LOS) at index admission. METHODS: This is a prospective, nation-wide, multi-center cohort study of Singaporean residents aged ≥55 years admitted for ≥48 hours after blunt injury with an injury severity score or new injury severity score ≥10, or an Organ Injury Scale ≥3, in public hospitals from 2016-2018. Demographics, mechanism of injury and frailty were recorded and analysed by Chi-square, or Kruskal-Wallis as appropriate. RESULTS: 218 participants met criteria and survived the index admission. Low fall patients had the highest proportion of frailty (44, 27.3%), followed by higher level fallers (3, 21.4%) and motor vehicle accidents (1, 2.3%) (p < .01). Injury severity, extreme age, and surgery were independently associated with longer LOS. Frail patients were paradoxically noted to have shorter LOS (p < .05). CONCLUSION: Patients sustaining moderate or severe injury after low falls are more likely to be frail compared to patients injured after higher-velocity mechanisms. However, this did not translate into longer adjusted LOS in hospital at index admission.


Assuntos
Idoso Fragilizado/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Ferimentos não Penetrantes/terapia , Acidentes por Quedas/estatística & dados numéricos , Acidentes de Trânsito , Idoso , Feminino , Fragilidade , Avaliação Geriátrica , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Singapura/epidemiologia , Ferimentos não Penetrantes/epidemiologia
4.
Sci Rep ; 9(1): 9248, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31239456

RESUMO

The objective of this study was to investigate the impact of levodopa therapy-induced complications on the quality of life (QoL) of Parkinson's disease (PD) patients in Singapore over a 1-year follow-up period. 274 PD patients were prospectively recruited, of which 78 patients completed the follow-up. Patients were evaluated on: (1) motor symptoms, (2) non-motor symptoms, (3) levodopa therapy-induced complications and (4) QoL. Levodopa-induced complications including dyskinesia and OFF symptoms occurred in 13.5% and 55.9% of the study population, respectively. In patients who completed the 1-year follow-up, there was a trend suggestive of increasing dyskinesia duration, more disabling dyskinesia as well as longer, more sudden and unpredictable OFF periods. There was a significant decline in the overall QoL at follow-up, in particular, activities of daily living, emotional well-being, cognition and communication domains were the most affected. The multivariable analysis demonstrated that worsening of UPDRS IV total score over 1-year interval was associated with worsening in PDQ-Summary Index score (d = 0.671, p = 0.014). In conclusion, levodopa-induced complications had significant adverse impacts on QoL. This study substantiates the importance for clinicians to closely monitor and promptly manage levodopa therapy-induced complications that may arise in patients.


Assuntos
Antiparkinsonianos/efeitos adversos , Discinesia Induzida por Medicamentos/epidemiologia , Levodopa/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Qualidade de Vida , Índice de Gravidade de Doença , Atividades Cotidianas , Idoso , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/patologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Singapura/epidemiologia , Resultado do Tratamento
5.
BMC Cancer ; 18(1): 459, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29688843

RESUMO

BACKGROUND: Advanced cancer significantly impacts quality of life of patients and families as they cope with symptom burden, treatment decision-making, uncertainty and costs of treatment. In Singapore, information about the experiences of advanced cancer patients and families and the financial cost they incur for end-of-life care is lacking. Understanding of this information is needed to inform practice and policy to ensure continuity and affordability of care at the end of life. The primary objectives of the Cost of Medical Care of Patients with Advanced Serious Illness in Singapore (COMPASS) cohort study are to describe changes in quality of life and to quantify healthcare utilization and costs of patients with advanced cancer at the end of life. Secondary objectives are to investigate patient and caregiver preferences for diagnostic and prognostic information, preferences for end-of-life care, caregiver burden and perceived quality of care and to explore how these change as illness progresses and finally to measure bereavement adjustment. The purpose of this paper is to present the COMPASS protocol in order to promote scientific transparency. METHODS: This cohort study recruits advanced cancer patients (n = 600) from outpatient medical oncology clinics at two public tertiary healthcare institutions in Singapore. Patients and their primary informal caregiver are surveyed every 3 months until patients' death; caregivers are followed until 6 months post patient death. Patient medical and billing records are obtained and merged with patient survey data. The treating medical oncologists of participating patients are surveyed to obtain their beliefs regarding care delivery for the patient. DISCUSSION: The study will allow combination of self-report, medical, and cost data from various sources to present a comprehensive picture of the end-of-life experience of advanced cancer patients in a unique Asian setting. This study is responsive to Singapore's National Strategy for Palliative Care which aims to identify opportunities to meet the growing need for high quality care for Singapore's aging population. Results will also be of interest to policy makers and researchers beyond Singapore who are interested to understand and improve the end-of-life experience of cancer patients. TRIAL REGISTRATION: NCT02850640 (Prospectively registered on June 9, 2016).


Assuntos
Protocolos Clínicos , Estado Terminal/economia , Estado Terminal/epidemiologia , Custos de Cuidados de Saúde , Adulto , Idoso , Estado Terminal/psicologia , Gastos em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Vigilância em Saúde Pública , Qualidade de Vida , Índice de Gravidade de Doença , Singapura/epidemiologia , Estresse Psicológico , Adulto Jovem
6.
Respirology ; 22(3): 454-459, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27862645

RESUMO

BACKGROUND AND OBJECTIVE: Asthma control can be assessed with the Asthma Control Test (ACT) and a score of 20 or higher indicates good asthma control. Patients pay for their consultation and treatment in the fee-for-service primary healthcare system in Singapore. We hypothesized that achieving asthma control would result in lower asthma costs through reduced acute exacerbations, fewer physician consultations and lower lost productivity. The study compared the healthcare costs of patients who achieved asthma control and those with suboptimal asthma control based on ACT scores. Factors influencing asthma control and healthcare expenditure over time were also examined. METHODS: A total of 736 patients were enrolled into an asthma care programme in two polyclinics during 2008 and 2013. Direct costs of asthma management were derived from the frequency of polyclinic consultations, medication costs and hospitalization. Indirect costs were estimated from lost workdays due to exacerbations. The generalized estimating equation (GEE) approach was used to longitudinally model the factors associated with total healthcare expenditure. RESULTS: Patients with asthma control spent S$48 (US$36) more per doctor visit on asthma drugs (P < 0.01) but incurred S$65 (US$48) less per doctor visit in total costs (P < 0.01) than those with suboptimal asthma control. The savings from achieving asthma control for obese patients were greater than for normal-weight patients (S$42 or the equivalent of US$31; P < 0.05). CONCLUSION: Optimal asthma control was associated with reduced healthcare costs. An effective treatment regimen should also consider other modifiable factors such as weight control to achieve asthma control and eventually reduce asthma costs.


Assuntos
Asma/economia , Asma/prevenção & controle , Custos de Cuidados de Saúde/estatística & dados numéricos , Gastos em Saúde/estatística & dados numéricos , Atenção Primária à Saúde/economia , Prevenção Secundária/economia , Adulto , Idoso , Asma/complicações , Efeitos Psicossociais da Doença , Custos Diretos de Serviços/estatística & dados numéricos , Custos de Medicamentos/estatística & dados numéricos , Feminino , Hospitalização/economia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/economia , Singapura
7.
Eur Respir J ; 47(3): 801-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26647437

RESUMO

Research on asthma costs often focuses on estimating average asthma costs. Trends in asthma costs and patterns of medication use, especially for those who have been followed up and under treatment, have received much less attention. This study's objective was to document asthma costs over time for asthma patients who are enrolled in an asthma care programme in Singapore and to identify its predictors, using a 10-year longitudinal dataset.The study population comprised different cohorts of 939 asthma patients entering the programme at different times during 2004-2013. Average asthma costs were estimated and the trends over time examined graphically, within and across patient cohorts. Regression analyses were conducted to examine cost predictors, with a focus on the relationship between risk factors at programme enrolment and subsequent asthma costs.The results indicate that 10-year average annual asthma cost was GBP 341 per patient. The main drivers of costs were asthma medications and consultation fees. Use of combined inhaled corticosteroid/long-acting ß-agonist medications increased over time, but this was accompanied by declines in controller drug use, doctor visits and total asthma drug costs. Obesity, smoking and asthma severity were the main predictors of subsequent asthma costs, especially for females.


Assuntos
Corticosteroides/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Asma/economia , Custos de Medicamentos/tendências , Custos de Cuidados de Saúde/tendências , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade , Fatores de Risco , Índice de Gravidade de Doença , Singapura , Fumar , Adulto Jovem
8.
NPJ Prim Care Respir Med ; 25: 15064, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26511220

RESUMO

BACKGROUND: Nocturnal asthma symptoms result in poor quality of life and morbidity. AIMS: This study primarily examines key factors predicting and mitigating nocturnal symptom risks among asthma patients, who were enrolled into a Singapore publicly funded asthma care programme. It also studies the association between nocturnal symptoms and medication changes as the secondary outcome. METHODS: A longitudinal study was conducted on 939 multi-racial Asian patients with persistent asthma. Patient clinical and therapeutic data were retrieved retrospectively from the programme's database established in 2004. Association between nocturnal symptoms (defined as night-time cough, wheeze and breathlessness at least twice monthly) and each categorical predictor was tested. The generalised linear mixed-effects model (GLIMM) was used to model the primary and secondary outcomes. RESULTS: Having nocturnal asthma symptoms was significantly associated with the number of days with breathlessness, off usual activities and off work, and asthma severity at baseline (all P values <0.05). The asthma action plan (AAP) status is significantly associated with nocturnal symptoms after adjusting for race, age and smoking status at baseline (odds ratio (OR)=0.49 (updated asthma action plan versus none), OR=0.37 (been-on plan versus none)). The risks of nocturnal asthma symptoms increased over time for those with allergic rhinitis (OR=1.52) and reduced with subsequent visits (OR=0.91). Nocturnal symptoms increased the odds (OR=2.87) of switching from inhaled corticosteroid (ICS) to combination medications (ICS-LABA (long-acting ß2-agonist)). CONCLUSIONS: The risks of having nocturnal symptoms were primarily associated with those with allergic rhinitis. An increase in patients' nocturnal symptoms was also predictive of the switching from ICS medications to combination formulations by their physicians.


Assuntos
Povo Asiático , Asma/fisiopatologia , Tosse/fisiopatologia , Dispneia/fisiopatologia , Atenção Primária à Saúde , Sons Respiratórios/fisiopatologia , Administração por Inalação , Corticosteroides/uso terapêutico , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Adulto , Idoso , Antiasmáticos/uso terapêutico , Asma/complicações , Asma/tratamento farmacológico , Tosse/etiologia , Substituição de Medicamentos , Quimioterapia Combinada , Dispneia/etiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sons Respiratórios/etiologia , Estudos Retrospectivos , Rinite Alérgica/complicações , Singapura , Fatores de Tempo , Adulto Jovem
9.
Parkinsonism Relat Disord ; 21(8): 843-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25997863

RESUMO

BACKGROUND: Non-motor symptoms (NMS) are common among patients with Parkinson's disease (PD) however little is known about their progression in terms of severity or burden after referral to expert care. OBJECTIVE: This study was aimed to establish the progression of NMS burden in PD patients after referral to tertiary healthcare centre and factors affecting it. METHODS: Newly referred PD patients were prospectively enrolled and follow-up for up to 18 months. Non-motor symptoms scale (NMSS) was used to evaluate the burden of non-motor symptoms. RESULTS: There was a significant median reduction of total NMS burden over the follow-up period. Similarly all NMS domains except domains 2 (sleep/fatigue), 3 (mood/cognition), 6 (gastrointestinal) and 7 (urinary) showed significant median reduction of scores. In the univariate regression analysis, Hoehn & Yahr staging, disease duration, visit, Schwab & England Activities of Daily Living score and UPDRS motor scores were individually predictive of change in total NMS burden. However, in the multivariable regression analysis only the latter three were significantly predictive of change in the total NMS burden. CONCLUSION: There was a significant reduction of total NMS burden over the study period. The severity of motor and activity of daily living impairments as well as subsequent visit were the best predictors of NMS change.


Assuntos
Progressão da Doença , Doença de Parkinson/fisiopatologia , Índice de Gravidade de Doença , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Encaminhamento e Consulta , Atenção Terciária à Saúde
10.
J Oral Maxillofac Surg ; 73(7): 1328-40, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25914133

RESUMO

PURPOSE: This prospective observational cohort study sought to determine the prevalence of inferior alveolar nerve (IAN) injury after mandibular fractures before and after treatment and to elucidate factors associated with the incidence of post-treatment IAN injury and time to normalization of sensation. MATERIALS AND METHODS: Consenting patients with mandibular fractures (excluding dentoalveolar, pathologic, previous fractures, or mandibular surgery) were prospectively evaluated for subjective neurosensory disturbance (NSD) and underwent neurosensory testing before treatment and then 1 week, 1.5, 3, 6, and 12 months after treatment. RESULTS: Eighty patients (men, 83.8%; mean age, 30.0 yr; standard deviation, 12.6 yr) with 123 mandibular sides (43 bilateral) were studied. Injury etiology included assault (33.8%), falls (31.3%), motor vehicle accidents (25.0%), and sports injuries (6.3%). Half the fractures (49.6%) involved the IAN-bearing posterior mandible; all condylar fractures (13.0%) had no NSD. Treatment included open reduction and internal fixation (ORIF; 74.8%), closed reduction and fixation (22.0%), or no treatment (3.3%). Overall prevalence of IAN injury was 33.7% (95% confidence interval [CI], 24.8-42.6) before treatment and 53.8% (95% CI, 46.0-61.6) after treatment. In the IAN-bearing mandible, the prevalence was 56.2% (95% CI, 43.2-69.2) before treatment and 72.9% (95% CI, 63.0-82.7) after treatment. In contrast, this prevalence in the non-IAN-bearing mandible was 12.6% (95% CI, 4.1-21.1) before treatment and 31.6% (95% CI, 20.0-43.3) after treatment. Factors associated with the development of post-treatment IAN injury included fracture site and gap distance (a 1-mm increase was associated with a 27% increase in odds of post-treatment sensory alteration). Time to normalization after treatment was associated with type of treatment (ORIF inhibited normalization) and fracture site (IAN-bearing sites took longer to normalize). CONCLUSION: IAN injury was 4 times more likely in IAN-bearing posterior mandibular fractures (56.2%) than in non-IAN-bearing anterior mandibular fractures (12.6%). After treatment, IAN injury prevalence (in 12 months) was higher (72.9% in posterior mandible, 31.6% in anterior mandible).


Assuntos
Fraturas Mandibulares/complicações , Nervo Mandibular/patologia , Traumatismos do Nervo Trigêmeo/etiologia , Acidentes por Quedas , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Traumatismos em Atletas/complicações , Queixo/inervação , Estudos de Coortes , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Humanos , Lábio/inervação , Masculino , Fraturas Mandibulares/classificação , Fraturas Mandibulares/terapia , Pessoa de Meia-Idade , Limiar da Dor/fisiologia , Complicações Pós-Operatórias , Estudos Prospectivos , Recuperação de Função Fisiológica/fisiologia , Limiar Sensorial/fisiologia , Tato/fisiologia , Violência , Adulto Jovem
11.
J Am Stat Assoc ; 106(493): 178-190, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21666842

RESUMO

An inverse regression methodology for assessing predictor performance in the censored data setup is developed along with inference procedures and a computational algorithm. The technique developed here allows for conditioning on the unobserved failure time along with a weighting mechanism that accounts for the censoring. The implementation is nonparametric and computationally fast. This provides an efficient methodological tool that can be used especially in cases where the usual modeling assumptions are not applicable to the data under consideration. It can also be a good diagnostic tool that can be used in the model selection process. We have provided theoretical justification of consistency and asymptotic normality of the methodology. Simulation studies and two data analyses are provided to illustrate the practical utility of the procedure.

12.
Exp Eye Res ; 89(6): 824-32, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19635475

RESUMO

The goal was to determine the age-related changes in accommodative movements of the lens and ciliary body in rhesus monkeys. Varying levels of accommodation were stimulated via the Edinger-Westphal (E-W) nucleus in 26 rhesus monkeys, aged 6-27 years, and the refractive changes were measured by coincidence refractometry. Centripetal ciliary process (CP) and lens movements were measured by computerized image analysis of goniovideographic images. Ultrasound biomicroscopy (UBM) at 50 MHz was used to visualize and measure accommodative forward movements of the ciliary body in relation to age, accommodative amplitude, and centripetal CP and lens movements. At approximately 3 diopters of accommodation, the amount of centripetal lens movement required did not significantly change with age (p = 0.10; n = 18 monkeys); however, the amount of centripetal CP movement required significantly increased with age (p = 0.01; n = 18 monkeys), while the amount of forward ciliary body movement significantly decreased with age (p = 0.007; n = 11 monkeys). In the middle-aged animals (12-16.5 years), a greater amount of centripetal CP movement was required to induce a given level of lens movement and thereby a given level of accommodation (p = 0.01), compared to the young animals (6-10 yrs). Collectively, the data suggests that, with age, the accommodative system may be attempting to compensate for the loss of forward ciliary body movement by increasing the amount of centripetal CP movement. This, in turn, would allow enough zonular relaxation to achieve the magnitude of centripetal lens movement necessary for a given amplitude of accommodation.


Assuntos
Acomodação Ocular/fisiologia , Envelhecimento/fisiologia , Corpo Ciliar/fisiologia , Cristalino/fisiologia , Presbiopia/fisiopatologia , Animais , Corpo Ciliar/diagnóstico por imagem , Corpo Ciliar/fisiopatologia , Modelos Animais de Doenças , Feminino , Gonioscopia/métodos , Cristalino/fisiopatologia , Macaca mulatta , Masculino , Microscopia Acústica , Movimento/fisiologia
13.
Invest Ophthalmol Vis Sci ; 47(3): 1076-86, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16505044

RESUMO

PURPOSE: The underlying causes of presbyopia, and the functional relationship between the ciliary muscle and lens during aging are unclear. In the current study, these relationships were studied in rhesus monkeys, whose accommodative apparatus and age-related loss of accommodation are similar to those in humans. METHODS: Centripetal ciliary body and lens equator movements were measured during accommodation in 28 eyes of 21 rhesus monkeys (ages, 5.7-26 years) by goniovideography. Ultrasound biomicroscopy was performed in 21 eyes of 17 monkeys. Narrowing of the angle between the anterior aspect of the ciliary body and the inner aspect of the cornea was used as a surrogate indicator of forward ciliary body movement during accommodation. RESULTS: Average centripetal ciliary body movement in older eyes (age > or =17 years, n = 16) was approximately 20% (0.09 mm) less than in young eyes (age, 6-10 years, n = 6), but not enough to explain the 60% (0.21 mm) loss in centripetal lens movement nor the 76% (10.2 D) loss in accommodative amplitude. Average forward ciliary body movement was 67% (49 degrees ) less in older (n = 11) versus young (n = 6) eyes. Maximum accommodative amplitude correlated significantly with the amplitude of centripetal lens movement (0.02 +/- 0.003 mm/D; n = 28; P < 0.001) and with forward ciliary body movement (3.34 +/- 0.54 deg/D; n = 21; P = 0.01). CONCLUSIONS: Decreased lens movement with age could be in part secondary to extralenticular age-related changes, such as loss of ciliary body forward movement. Ciliary body centripetal movement may not be the limiting component in accommodation in the older eye.


Assuntos
Acomodação Ocular/fisiologia , Envelhecimento/fisiologia , Corpo Ciliar/fisiologia , Iridectomia , Cristalino/fisiologia , Ligamentos/fisiologia , Macaca mulatta/fisiologia , Animais , Corpo Ciliar/diagnóstico por imagem , Movimentos Oculares , Feminino , Gonioscopia , Cristalino/diagnóstico por imagem , Ligamentos/diagnóstico por imagem , Masculino , Microscopia Acústica , Músculo Liso/diagnóstico por imagem , Músculo Liso/fisiologia
14.
Invest Ophthalmol Vis Sci ; 47(3): 1087-95, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16505045

RESUMO

PURPOSE: To document zonular orientation and suspension of the lens during accommodation, and age-related changes of the circumlental space (CLS) at rest and during accommodation, in living iridectomized rhesus monkey eyes. METHODS: The CLS was measured in 34 iridectomized eyes of 24 living rhesus monkeys, age 5.7 to 26 years, in the resting and accommodated state, and the orientation of the zonula and suspension of the lens during accommodation was assessed qualitatively. RESULTS: The nonaccommodated CLS decreased significantly with age in both the nasal and temporal quadrants and tended to do so at a slightly faster rate in the temporal quadrant. The CLS correlated significantly with the accommodative amplitude: the greater the CLS the greater the accommodative amplitude. Multiple regression analysis indicated that age and CLS together are better predictors of accommodative amplitude than is age alone. The zonula appeared taut in the nonaccommodated eye throughout the age range despite the age-related decline in CLS. CONCLUSIONS: Characterization of age-related changes in the accommodative apparatus may help to model the system for hypothesis testing. The CLS may be an indicator of presbyopia-related processes in surrounding tissues. However, these results do not prove that the width of the CLS, in and of itself, has a causal relationship with accommodative amplitude, or that changes in the CLS play a pathophysiological role in presbyopia.


Assuntos
Acomodação Ocular/fisiologia , Envelhecimento/fisiologia , Iridectomia , Cristalino/fisiologia , Ligamentos/fisiologia , Macaca mulatta/fisiologia , Animais , Feminino , Gonioscopia , Cristalino/ultraestrutura , Ligamentos/ultraestrutura , Masculino , Microscopia Acústica
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