We demonstrate: (1) procedures for collection of salivary samples in cognitive impaired older adults by family caregivers in the home setting, (2) procedures for measuring stress activity via salivary cortisol and alpha amylase, and (3) representative profiles. Protocols that allow researchers to study stress-linked processes advance our understanding of biological sensitivity and susceptibility.
Salivary measures have emerged in bio-behavioral research that are easy-to-collect, minimally invasive, and relatively inexpensive biologic markers of stress. This article we present the steps for collection and analysis of two salivary assays in research with frail, community residing older adults-salivary cortisol and salivary alpha amylase. The field of salivary bioscience is rapidly advancing and the purpose of this presentation is to provide an update on the developments for investigators interested in integrating these measures into research on aging. Strategies are presented for instructing family caregivers in collecting saliva in the home, and for conducting laboratory analyses of salivary analytes that have demonstrated feasibility, high compliance, and yield quality specimens. The protocol for sample collection includes: (1) consistent use of collection materials; (2) standardized methods that promote adherence and minimize subject burden; and (3) procedures for controlling certain confounding agents. We also provide strategies for laboratory analyses include: (1) saliva handling and processing; (2) salivary cortisol and salivary alpha amylase assay procedures; and (3) analytic considerations.
The theoretical perspective guiding lifespan developmental science emphasizes the need to integrate biological, behavioral, social, and contextual factors into the study of health and behavior1. Contemporary theoretical models champion the notion that individual differences in biological sensitivity and susceptibility to contextual factors may moderate risk versus resilience, and can forecast morbidity and mortality in vulnerable populations. Considerable research attention has focused on these issues early in life development1, but only recently have investigators been able to test the core ideas in studies with medically and cognitively frail older adults2-4. One reason for this trend is the development of procedures to noninvasively measure differences in neurobiological activity including the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) within and across individuals via oral fluids (saliva)5,6.
Salivary measures can allow for the collection of normative longitudinal data, to compare changes between different treatment groups, to compare effectiveness of interventions, or can be extended to include measurement of coregulation or activity between multiple individuals. The data obtained from these measures can shed light on stress-linked biological processes in health conditions common in older adults including cancer, heart disease or neurocognitive disorders7. Saliva has received growing attention as a biospecimen due to the perceptions of sample collection as an easy to learn, inexpensive, minimally invasive, and acceptable8. Nonetheless, the conventional methods of collection requiring participants to drool through a straw into a small tube have been shown to be too complicated or undesirable for older, frail participants. New methods are required that can standardize the preanalytical phase of collection and processing to deliver the most accurate and meaningful results. The field of salivary bioscience is advancing rapidly and the purpose of this presentation is to provide an update of developments and a practical roadmap for investigators interested in integrating these measurement approaches into research on aging. In this protocol we demonstrate (1) procedures for collection of salivary samples in cognitive impaired older adults by family caregivers in the home setting, (2) the procedures for measuring HPA axis and ANS activity via salivary cortisol and salivary alpha amylase (sAA), and (3) representative individual differences in salivary cortisol and sAA data.
To advance our understanding of the meaning of individual differences in biological sensitivity and susceptibility in frail older adults investigators will need to engage caregivers in the collection of biological specimens. These collection protocols need to be minimally invasive, easy to accomplish, and yield quality specimens. Since one major challenge is ensuring that caregivers collect the samples at the correct time family caregivers designated as saliva collectors should be screened for ability to understand writt…
The authors have nothing to disclose.
Study funded by NINR, K23NR012017-01A1 Adrenocortical Response and Neuro-psychiatric Symptoms in Alzheimer's Disease.
Salimetrics Children Swab (SCS) | Salimetrics | 5001.06 | store at RT 50/pack |
Swab storage tube (2 ml) | Sarstedt | 51.1534.004 | 100/pack |
Barcode lables | CISBR | n/a | contact CISBR to order |
Color coded polypropylene vial caps (for SST) | Sarstedt | (see below) | |
White | Sarstedt | 65.793.517 | 1,000/pack |
Blue | Sarstedt | 65.793.513 | 1,000/pack |
Yellow | Sarstedt | 65.793.514 | 1,000/pack |
Green | Sarstedt | 65.793.515 | 1,000/pack |
Orange | Sarstedt | 65.793.516 | 1,000/pack |
Red | Sarstedt | 65.793.518 | 1,000/pack |
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Violet | Sarstedt | 65.793.520 | 1,000/pack |
Mixed Colors | Sarstedt | 65.793.999 | 1,000/pack |
Salivary Cortisol Enzyme Immuno Assay Kit | Salimetrics | 1.3102 | Diagnostic Kit |
Salivary Alpha Amylase Enzyme Immuno Assay Kit | Salimetrics | 1.1902 | |
Nitrile gloves | VWR | (see below) | |
X-Small | VWR | 82026-423 | 100/box |
Small | VWR | 82026-424 | 100/box |
Medium | VWR | 82026-426 | 100/box |
Large | VWR | 82026-428 | 100/box |
X-Large | VWR | 82026-43 | 100/box |
Insulated Shipping Container | ThermoFisher | Varies based on size | Visit VWR to select size and order |
4 in Sample Storage Box (7 x 7) | Sarstedt | 95.064.949 | 1 box holds 49 SSTs |