Curso de Farmacologia clínica: Alterações Farmacológicas em idosos (Parte II)

Summary

The video discusses the impact of adverse drug reactions (ADRs), which are a leading cause of death, surpassing conditions like diabetes and cardiovascular diseases. It highlights the high costs of ADRs and the increased susceptibility of elderly individuals due to age-related physiological changes, such as reduced body water and muscle mass. These factors affect drug distribution, metabolism, and elimination, making older adults more prone to severe reactions. The video emphasizes the need for awareness and proper care to prevent ADRs, as well as the specific functional changes in elderly tissues that influence drug effects.

Takeaways

• 😀 Adverse drug reactions (ADRs) are the fourth leading cause of death, surpassing diseases like diabetes and pulmonary diseases, with 100,000 deaths annually due to ADRs.
• 😀 ADRs also lead to significant costs, totaling around $136 billion annually, with severe reactions costing millions more in healthcare resources.
• 😀 ADRs increase hospital stays, doubling both the duration and associated costs, as well as contributing to twice the mortality rate in hospitalized patients.
• 😀 Elderly patients are particularly vulnerable to ADRs due to age-related changes in their bodies, which impact how medications are distributed and metabolized.
• 😀 One key physiological change in the elderly is the reduction in body water, which affects the distribution of water-soluble drugs, making them remain in the bloodstream longer.
• 😀 Muscle mass declines with age, leading to a reduction in the distribution of drugs that rely on muscle mass for proper distribution, causing them to remain in higher concentrations in the bloodstream.
• 😀 Older adults experience an increase in body fat, which affects the distribution of fat-soluble drugs, leading to longer retention in fat cells and prolonged drug effects.
• 😀 Albumin levels decrease with age, reducing the amount of protein available to transport drugs, leading to higher levels of free drugs in the bloodstream, which can increase their pharmacological effects.
• 😀 Hepatic function declines in elderly individuals, resulting in reduced metabolism and biotransformation of medications, which can lead to drug interactions and increased drug half-life.
• 😀 Renal function also decreases with age, reducing the elimination of drugs and leading to longer drug circulation and higher risks of toxicity and adverse effects.
• 😀 Pharmacokinetic changes in the elderly, including slower absorption, delayed gastric emptying, reduced intestinal blood flow, and diminished surface area for drug absorption, all impact the effectiveness and safety of medications.

Q & A

What are the main consequences of adverse drug reactions (ADRs) according to the script?

Adverse drug reactions are a significant cause of mortality, being the fourth leading cause of death, surpassing conditions like diabetes mellitus and certain respiratory diseases. They also carry a high cost, totaling around 136 billion dollars annually, and lead to increased hospitalization time and mortality rates.

How do adverse drug reactions impact patients in long-term care facilities?

Approximately 350,000 patients with adverse drug reactions reside in nursing homes, highlighting the vulnerability of elderly populations to such reactions.

What specific factors make older adults more susceptible to adverse drug reactions?

Older adults have several physiological changes, such as reduced body water, lower lean body mass, increased adipose tissue, and decreased albumin levels. These changes alter drug distribution, prolong drug presence in the bloodstream, and increase the likelihood of adverse effects.

How does the reduction in body water impact drug distribution in the elderly?

In elderly individuals, the proportion of body water decreases, affecting the distribution of hydrophilic drugs. These drugs remain in the bloodstream for longer periods, potentially leading to higher concentrations and increased risk of adverse reactions.

How does reduced lean body mass affect pharmacokinetics in older adults?

With a decrease in lean body mass, hydrophilic drugs, which rely on both body water and lean tissue for distribution, may remain in the bloodstream for longer periods, increasing the potential for adverse effects.

What is the role of increased adipose tissue in drug distribution in older adults?

Increased fat tissue in older adults facilitates the distribution of lipophilic drugs, causing these drugs to remain stored in adipocytes and prolonging their effects, potentially leading to adverse drug reactions.

Why does a decrease in albumin levels pose a risk in the elderly?

Albumin is a key protein responsible for transporting drugs in the bloodstream. A decrease in albumin levels means there are fewer carriers for drugs, leading to an increased proportion of free, pharmacologically active drugs in the bloodstream, which heightens the risk of adverse reactions.

What are the main changes in liver function that impact drug metabolism in older adults?

In the elderly, there is a decline in liver function due to reduced blood flow, loss of liver tissue, and diminished regenerative capacity. These changes affect the metabolism of drugs, potentially leading to slower biotransformation and altered drug activity.

How does cardiovascular aging influence drug efficacy in older adults?

Cardiovascular aging leads to a decrease in the number of beta receptors in the heart, affecting how drugs that interact with these receptors, such as beta blockers, work. Reduced receptor affinity and responsiveness can make drugs less effective in older individuals.

How does reduced kidney function impact drug elimination in the elderly?

Aging leads to a decline in renal function, including reduced glomerular filtration rate and blood flow to the kidneys. This slows the elimination of drugs, allowing them to remain in the body longer, increasing the risk of toxicity and adverse effects.