Tactile Perception and Advanced Age: Evaluation in a Specific Group of Elderly

Purpose: Changes of sensory tactile perception are a modification in the ability of capture and interpret external stimuli by the sense of touch. Sensory evaluation allows the recognition of abnormalities, showing the nervous damage. Degenerative changes that occur in elderly’s skin determine the reduction of exteroceptive receptors or cutaneous receptors, causing a lower perception of ambient temperature and variations, as well as the reduction of tactile sensitivity. Therefore, the evaluation of tactile perception must include senior care, whereas many of them will have disorders of perception, which may compromise their ability to execute daily activities.  The aim of this study was to evaluate the tactile perception in elderly. 

Methods: A cross-sectional study performed from November to December 2014 in Fortaleza, Brazil, in a private social institution that improves the quality of life of its members, including the elderly. The population consisted of 65 elderly of both sexes. The following inclusion criteria were used: to present age equal or over 60 years; have preserved mental status and alert; be able to verbalize and execute commands. It was excluded those individuals who did not have time available to participate in the study or refused to participate for another reason. The sample was selected by convenience. In order to collect the data it was used two instruments. The first one was elaborate for this study and it was intended to investigate the elderly’s socioeconomic and clinical characteristics and also the elderly living habits and evaluate their functional capacity. Thus, it included gender, age, hometown, marital status, family income, current and previous occupation, education, comorbidities, smoking, alcohol consumption habit, habit of physical activity, occur of change in skin, balance and grip strength. The evaluation of the functional capacity of the elderly was done by investigating the basic daily Life activities by Barthel Scale and the evaluation of instrumental activities of daily living by the Lowton and Brody Instrumental Activities of Daily Living Scale. The second instrument, specific to evaluate the tactile perception, was adapted from previous study and investigated eight sensory modalities (light touch, pressure, temperature, tactile location, two-point discrimination, stereognosis, texture and extinction of a simultaneous stimulation) by using different resources. The sensory perception was identified in facial regions, hands and feet. All students and nurses who was involved in data collection were previously trained by a doctoral student in order to reduce the possible bias of the study. After the data was collected, descriptive statistical analysis was performed with arithmetic mean and standard deviation for numerical variables. Absolute and relative frequencies were used to nominal variables. The study was submitted to the Ethics Committee of the Federal University of Ceara, protocol N. 851.449. Terms of consent were signed by the patients who accepted to participate in the study. 

Results: In the 65 investigated elderly, there was a predominance of women (89.2%) with a mean age of 70.6 (± 6.59) years, average familiar income of $1.046,62 (± 816,32), average education of 11, 8 (± 5.0) years; of these only 15.8 % have a partner. By the average family income and years of education, it can be considered that this is a group of middle-class elderly with a good level of education, which can positively affect the health self-care, the control of comorbidities and the prevention of complications. Even so, 63% have arterial hypertension and 16.7% diabetes. The presence of diabetes has relevance for this study, whereas it is a factor that causes deficits in tactile perception. Despite the comorbidities, it can be assumed that most of the participants of the study adopt a lifestyle that can be classified as a healthy pattern, through regular physical activity (81.5%), the absence of the intake of alcoholic beverages (80%) and the absence of smoking habits in most individuals (64.5%). It is considered that this lifestyle is a protective factor for the adaptation of intrinsic aging changes, among them the tactile perception. In the physical evaluation, most of the elderly (81.5%) had no change in skin and negative results in the investigation of balance through the Romberg test (85.9%). All the participants were considered independents in the functional capacity evaluation, both in relation to basic and instrumental activities of daily living. The results of the tactile perception of the face show few changes, standing out somatosensory discrimination (38.5%), investigated by the two-point discrimination test. In the evaluation of tactile sensory function in hands it was observed changes in predominant distinguish of two points (76.9%), showing that the test adopted has highly sensitive detection for sensory dysfunction. Other disorders of tactile perception in the hands evaluation have been identified by monofilament pressure (23.1%), by the test with different temperatures (21.5%), and by responses to the examiner's hand pressure (15.4%). The investigation of tactile perception in the region of the feet showed more changes in all tests when compared to the results of the evaluations of the face and hands. The most prevalent changes were detected in the two-point difference test (84.9%) and thermal sensitivity test (70.8%), but other tests also demonstrated changes. In texture tests, stereognosis and simultaneous stimulus few changes were identified. The results reinforce the idea that the change in tactile function is intrinsic to aging and may be aggravated by the appearance of any comorbidities such as diabetes, found in 16.7% of study participants. The study revealed few changes in tactile perception of light touch, pressure and tactile location. Similar results were shown in the evaluation with cotton and monofilament for light touch, also using the examiner's hand and monofilament for pressure perception assessment. It was identified larger proportion of changes in the thermal sensitivity in the region of the foot (70.8%), which indicates the relevance of the inclusion of this test to evaluate this form of sensitivity, whereas it has not yet been established as a standard in the evaluation of tactile function. It was predominant the changes in the distinction between two points on the hands (76.9%) and feet (84.9%), showing to be a highly sensitive test, which is a different result comparing with other studies.

Conclusion: It is clear that although sensory loss is a process associated with aging, adherence to a healthy and active lifestyle influences the mitigation and adaptation of these losses, as a compensatory mechanism. That brings benefits to the elderly as preserving their functionality, associated with maintaining balance and gait and preventing damage to the skin. As limitations of this study, stands out the difficult to generalize the results due to the small amount of similar studies published. It is expected that the results of this study subsidize the improvement of nursing knowledge about this subject.