Review the Resources for this module and consider the impact of potential pharmacotherapeutics for cardiovascular disorders introduced in the media piece.
Review the case study assigned by your Instructor for this Assignment.
Select one the following factors: genetics, gender, ethnicity, age, or behavior factors.
Reflect on how the factor you selected might influence the patient’s pharmacokinetic and pharmacodynamic processes.
Consider how changes in the pharmacokinetic and pharmacodynamic processes might impact the patient’s recommended drug therapy.
Think about how you might improve the patient’s drug therapy plan based on the pharmacokinetic and pharmacodynamic changes. Reflect on whether you would modify the current drug treatment or provide an alternative treatment option for the patient. Write a 2- to 3-page paper that addresses the following:

Explain how the factor you selected might influence the pharmacokinetic and pharmacodynamic processes in the patient from the case study you were assigned.
Describe how changes in the processes might impact the patient’s recommended drug therapy. Be specific and provide examples.
Explain how you might improve the patient’s drug therapy plan and explain why you would make these recommended improvements.

Pharmacotherapy for Cardiovascular Disorders

The patient in the case study is a female octogenarian of 86 years of age. She has multiple comorbidities but currently has been admitted with delirium which is an indication that she is also having a neurodegenerative disorder that is only now showing symptoms. She has a history of hypertension, osteoarthritis, gastroesophageal reflux disease (GERD), and chronic kidney disease. What is striking is that she is on a poly pharmaceutical regime of six medications despite her age. She is getting digoxin, metoprolol, warfarin, APAP, multivitamin and omeprazole. It is a known fact that with advanced age, the bodily processes that are essential for medications to be processed and metabolites excreted after their half-life become less effective. This means that giving many drugs at one go (polypharmacy) will be risky for such a patient and especially one who is 86 years old (Kim & Parish, 2017). Moreover, even if the patient were to be given less medications, these may have to be reduced in dose because of the effect of age on the pharmacokinetics (PK) and pharmacodynamics (PD) of drugs (Peeters et al., 2019). Pharmacokinetics refers to the effect that bodily processes have on drugs when they are administered into the human body. Pharmacodynamics on the other hand refers to the effect that medications through their mechanisms of action have on the body (Katzung, 2018; Rosenthal & Burchum, 2018). Apart from age, the other factors that affect the PK and PD of medications in the body are genetics, ethnicity, behavioral factors, and gender. The purpose of this paper is to examine the effect that age has on the PK and PD of drugs; within the context of the medications given to this octogenarian.

The Relationship Between Age and the Pharmacokinetics and Pharmacodynamics of Drugs

Aging slows down all bodily processes such that physiology slows down and metabolism also reduces in efficacy. In terms of pharmacodynamics, the deterioration of the elderly patent’s body systems and functions will make them weak and frail such that the normal actions of drugs may overwhelm them. Whereas a youthful person would withstand and tolerate the therapeutic effects of a medication, an elderly person such as this octogenarian may find it hard to cope and even suffer undesired consequences. This is one of the reasons as to why it may be prudent to first avoid polypharmacy in them and then to reduce the drug doses prescribed to them. This will especially be true with regard to digoxin and metoprolol as they mediate very crucial functions such as blood pressure and the contractility of the heart.  Pharmacotherapy for Cardiovascular Disorders Essay Paper

On pharmacokinetics, the processes concerned have been given the acronym ADME. This means absorption, distribution, metabolism, and excretion (Katzung, 2018; Rosenthal & Burchum, 2018). The gastrointestinal tract (GIT) of elderly patients just like all other body systems deteriorates with age. Yet all medications taken orally have to be absorbed through the GIT. For instance, the protein channels that aid the absorption of drugs in the gut usually deteriorate in function as one ages. This means that they can no longer absorb drugs from the gut as efficiently as before. The net result is that there will be less bioavailability of the medication as fewer quantities will get into the body and be distributed to tissues. This must be taken into account when prescribing for the elderly.

The distribution of medications also suffers because of age in pharmacokinetics. Drugs are either water soluble (hydrophilic) or fat-soluble (lipophilic). Ageing reduces lean body mass as well as adipose tissue. For this reason alone, the distribution of medications in the body of an old person is not efficient (Peeters et al., 2019). The implication of this is that for this 86 year-old patient the doses of digoxin, metoprolol, warfarin, APA, and omeprazole have to be reduced to guard the safety of the patient. Then there is the process of metabolism of medications into active metabolites. All of the medications that are taken orally as in the case of this patient have to go through the liver through what is known as the first pass effect. It is in the liver that they are metabolized by enzymes referred to as the cytochrome P450 isoenzymes. Unfortunately for the elderly, the efficacy of these enzymes reduces significantly as one grows older. It would therefore be expected that in an octogenarian of 86 years old the enzyme function is markedly reduced. For this reason too, the doses of the six medications this patient is on must be reduced for her own safety.

Lastly but not least is excretion. The estimated glomerular filtration rate or eGFR is known to decline with age. At 86 years old, this patient has the lowest eGFR and this is confirmed by the fact that she has chronic kidney failure or CKD already diagnosed (Hammer & McPhee, 2018; Huether & McCance, 2017). For this patient, particular attention has to be given to digoxin that is eliminated from the body principally by renal excretion. In actual fact, the excretion of digoxin from the body is closely associated with the glomerular filtration rate. Since this is already very low, the dose must be drastically lowered or the patient must undergo renal replacement therapy such as dialysis.

The Impact on the Patient’s Drug Therapy Plan

The impact of the above on the patient’s drug therapy plan is that first and foremost she should be removed from the polypharmacy as it is counterproductive. Second, all the drug doses will have to be lowered to prevent her from suffering toxicity. For instance, Buelt et al. (2021) opine that for elderly patients with hypertension, the drug doses for hypertensives that they should be started on should be half or even quarter of the usual drug doses.

Conclusion

In all, age is a factor that strongly affects the way the body treats drugs and also the way that drugs treat the body. Since body systems in the elderly are reduced in efficacy, it is not safe to put them on more than five medications as this would now be polypharmacy. As a rule therefore, all drug doses need to be decided carefully and those that need to be reduced done so immediately to avoid adverse events.

References

Buelt, A., Richards, A., & Jones, A. (2021). Hypertension: New guidelines from the international Society of Hypertension. American Family Physician, 103(12), 763-765. https://www.aafp.org/pubs/afp/issues/2021/0615/p763.html

Hammer, D.G., & McPhee, S.J. (Eds). (2018). Pathophysiology of disease: An introduction to clinical medicine, 8^th ed. McGraw-Hill Education.

Huether, S.E. & McCance, K.L. (2017). Understanding pathophysiology, 6^th ed. Elsevier, Inc.

Katzung, B.G. (Ed) (2018). Basic and clinical pharmacology, 14^th ed. McGraw-Hill Education.

Kim, J., & Parish, A.L. (2017). Polypharmacy and medication management in older adults. Nursing Clinics of North America, 52(3), 457–468. https://doi.org/10.1016/j.cnur.2017.04.007

Peeters, L.E.J., Kester, M.P., Feyz, L., Van Den Bemt, P.M.L.A., Koch, B.C.P., Van Gelder, T., & Versmissen, J. (2019). Pharmacokinetic and pharmacodynamic considerations in the treatment of the elderly patient with hypertension. Expert Opinion on Drug Metabolism & Toxicology, 15(4), 1–11. https://doi.org/10.1080/17425255.2019.1588249

Rosenthal, L.D., & Burchum, J.R. (2018). Lehne’s pharmacotherapeutics for advanced practice providers. Elsevier.

Pharmacotherapy for Cardiovascular Disorders Essay Paper