Related Experiment Video
Updated: Aug 15, 2026
06:21
Osmotic Minipump Implantation for Increasing Glucose Concentration in Mouse Cerebrospinal Fluid
Published on: April 7, 2023
Reduced survival with increasing plasma osmolality in elderly continuing-care patients
P A O'Neill1, E B Faragher, I Davies
1Department of Geriatric Medicine, University Hospital of South Manchester.
Age and Ageing
|January 1, 1990
Summary
High plasma osmolality in elderly patients significantly reduced survival in a 2-year study. This hyperosmolar state was linked to increased mortality, independent of age.
Area of Science:
- Gerontology
- Internal Medicine
- Clinical Research
Background:
- Elderly individuals in continuing-care units often present with complex health issues.
- Hyperosmolar states, characterized by elevated plasma osmolality, can indicate underlying physiological disturbances.
Purpose of the Study:
- To investigate the relationship between plasma osmolality and survival in elderly patients.
- To determine if hyperosmolality is a predictor of mortality in a frail elderly population.
Main Methods:
- A 2-year follow-up study involving 58 elderly patients in a continuing-care unit.
- Measurement of plasma osmolality at the time of patient entry.
- Analysis of survival rates and correlation with initial plasma osmolality levels.
Main Results:
- Most patients entered the study in a hyperosmolar state (mean plasma osmolality: 304 +/- 8 mOsmol/kg).
- Patients with the highest plasma osmolality (greater than 308 mOsmol/kg) showed significantly reduced survival (p = 0.025).
- Increased 2-year mortality was observed in patients with higher osmolality (15/20 patients, p = 0.053).
Conclusions:
- Elevated plasma osmolality is associated with significantly reduced survival in frail elderly patients.
- Hyperosmolality may serve as a marker for, or contribute to, increased mortality in this demographic.
- The effect of osmolality on survival was independent of patient age.
Related Concept Videos
02:40Osmosis and Osmotic Pressure of Solutions
A number of natural and synthetic materials exhibit selective permeation, meaning that only molecules or ions of a certain size, shape, polarity, charge, and so forth, are capable of passing through (permeating) the material. Biological cell membranes provide elegant examples of selective permeation in nature, while dialysis tubing used to remove metabolic wastes from blood is a more simplistic technological example. Regardless of how they may be fabricated, these materials are generally...
01:22Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Absorption
As individuals age, their body's physiology evolves, affecting drug pharmacokinetics. The most apparent changes occur in the gastrointestinal tract, where an increase in gastric pH, a delay in gastric emptying, and a reduction in gastrointestinal motility are observed. Remarkably, these changes do not substantially modify the absorption of orally administered drugs, particularly those absorbed via passive diffusion.Transdermal drug delivery emerges as a highly viable method for older adults due...
01:00Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Distribution
Drug distribution in the human body is influenced by several factors, including plasma protein concentration, body composition, blood flow, tissue-protein concentration, and tissue fluid pH. Among these, changes in plasma protein concentration and body composition due to aging significantly affect how drugs are distributed within the body. Specifically, aging is associated with a decrease in albumin levels by about 10% and an increase in α1-acid glycoprotein levels. These alterations are not...
01:18Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Excretion
In geriatric patients, renal physiology undergoes significant changes, including diminished renal blood flow and a lower glomerular filtration rate (GFR), leading to alterations in medication clearance. Drugs such as aminoglycoside antibiotics, lithium, and digoxin, which rely on glomerular filtration for removal from the body, particularly impact pharmacokinetics. These drugs tend to have slower clearance rates in older adults, necessitating careful dosage considerations.Evaluation of renal...
01:28Factors Influencing Microbial Growth: Osmolarity
Osmolarity is the measure of solute concentration in a solution. It plays a critical role in determining water availability for organisms. Water moves across semipermeable membranes through osmosis, flowing from regions of lower solute concentration (more dilute) to regions of higher solute concentration (more concentrated).In high-solute environments, microbial cells lose water, leading to dehydration and inhibited growth. The extent to which water is available to microbes in such environments...
01:21Hyperosmolar Hyperglycemic State
Hyperosmolar Hyperglycemic State, or HHS, is a serious and life-threatening complication of type 2 diabetes mellitus. It is characterized by three main features: severe hyperglycemia, profound dehydration, and elevated serum osmolality, all occurring without significant ketoacidosis.HHS typically develops in older adults or individuals with limited access to fluids. This may result from illness, cognitive impairment, or medications such as diuretics or corticosteroids. These factors reduce...