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A two-year study beginning in 1977 found that, among 85-year-old peopl

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jabhatta2

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02 Apr 2022, 16:51

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GMATGuruNY - how would you go about solving this ? i am not sure i unerstand what is expected off of me when i read the passage

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03 Apr 2022, 04:58

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Since immune system doesn't protect against heart disease, why don't we replace "weakest immune system" with "white hair" - just to make it easier for us to see what's surprising about this study's findings:

A two-year study beginning in 1977 found that, among 85-year-old people, those whose hair is white were twice as likely to die within two years as others in the study. The cause of their deaths was most often heart disease.

Which of the following, if true, would offer the best prospects for explaining why people with white hair were twice as likely to die as those without white hair?

(C) Some of the drugs that had been used to treat the symptoms of heart disease had a side effect of turning hair white.

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03 Apr 2022, 12:05

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jabhatta2

GMATGuruNY - how would you go about solving this ? i am not sure i unerstand what is expected off of me when i read the passage

When the question stem asks us to explain, the passage will generally offer two facts that seem to contradict each other.
The correct answer must EXPLAIN how both facts can be true at the same time.

Quote:

Fact 1:
Those whose immune systems were weakest were twice as likely to die.
Fact 2:
The cause of their deaths was more often heart disease, against which the immune system does not protect.

Quote:

Which of the following, if true, would offer the best prospects for explaining deaths in which weakness of the immune system, though present, played no causal role?

Given that the cause of death was typically heart disease -- against which the immune system does not protect -- why was there such a high correlation between a weakened immune system and death?
Only C offers a logical explanation:
Some of the drugs that had been used to treat the symptoms of heart disease had a side effect of weakening the immune system.

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17 Apr 2022, 10:31

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Why does (C) Some of the drugs that had been used to treat the symptoms of heart disease had a side effect of weakening the immune system solve the paradox?

If those people took these drugs, they should not die and got effect of weakening the immune system.

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17 Apr 2022, 10:35

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Tanchat

I think you're making a very big assumption about the drugs that we all wish were true about medicine, but isn't. Also notice what the drugs actually do ('treat the symptoms of heart disease') and what they don't do ('cure heart disease').

The reason this resolves the paradox is by explaining why people who died had lower immune systems, but died in a way that wasn't 'caused by' the weak immune system. If you learned that a disproportionate amount of people who died had weak immune systems, you might think, 'well, that's expected, because their immune system is weak!' And then you find out that the way they died *wasn't because of their weak immune system*, you'd wonder, 'then why what caused the disproportion?'

It turns out that the cause-of-death (heart disease) caused the weak immune system.

Reverse causation is a big thing to look out for on the GMAT. That and other common 'games' the GMAT plays in CR can be learned about here:

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04 Nov 2022, 05:09

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Dear GMATNinja

I have a trouble regarding this question
Question tells us that "those whose immune systems were weakest were twice as likely to die within two years as others in the study. The cause of their deaths, however, was more often heart disease than cancer or infections"

Here ı presume that "their" refers to the people at lowest immunity system strength spectrum. So, we understand that people with low immune systems are more likely to die but somehow more of them died due to heart attack than to infections...

Question asks us to identify the choice that may offer the best explanation that they died not because of weakness of the immune system

(A) There were twice as many infections among those in the study with the weakest immune systems as among those with the strongest immune systems.
If we say that people with the lowest immune system had more infections but still didn't die mostly to infections doesn't it solidify that weak immune system may not be the culprit? Because from the stem we know that majority cause for their death is heart attack but not infections

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28 Nov 2022, 16:11

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gloomybison

Take another look at the exact language of the question:

Quote:

Which of the following, if true, would offer the best prospects for explaining deaths in which weakness of the immune system, though present, played no causal role?

The question asks us to explain the deaths in which the weakness of the immune system "played no causal role." From the passage, we can infer that this means the deaths from heart disease. How can we explain these deaths? Why the heck are people with weak immune systems dying of heart disease, even though the immune system doesn't play a causal role?

That's pretty different than your paraphrase of "identify the choice that may offer the best explanation that they died not because of weakness of the immune system."

Keeping the exact language of the question in mind, we know that we're looking to explain what's going on with the people who died of heart disease.

Here's (A):

Quote:

(A) There were twice as many infections among those in the study with the weakest immune systems as among those with the strongest immune systems.

(A) tells us that people with weak immune systems got more infections than those with strong immune systems. This might explain more deaths from infection, but it doesn't tell us anything about deaths from heart disease. Because it doesn't provide an explanation for the exact conundrum presented in the passage, (A) is out.

Here's (C):

Quote:

(C) Some of the drugs that had been used to treat the symptoms of heart disease had a side effect of weakening the immune system.

Bingo! (C) tells us that some people already had heart disease, and the treatment of this heart disease caused them to have a weakened immune system. Is it so surprising that these people would be dying from heart disease? Nope, that makes sense -- the people who have to be treated for heart disease obviously HAVE heart disease, so they're more likely to die of heart disease. The immune system issue is just a side effect.

(C) explains the exact deaths that the question asks us to explain, so (C) is the correct answer.

I hope that helps!

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09 Dec 2022, 16:19

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Hi avigutman

Quote:

When you read the blue -

Do you comprehend that as saying

-- The STRONGER immune system, the lower likelihood of cancer/infections
-- The WEAKER immune system, the higher likelihood of cancer/infections

OR

Do you comprehend the blue as saying

-- There is some relationship between cancer/infections vs immune systems. But we cant say for sure -- The Stronger Immune system, the lower the likelihood of cancer/infections.
------------------------------------------------------------

Same question on the red

When you read the red - Do you comprehend that as saying

-- There is NO relationship/correlation between heart disease vs immune systems.

OR

-- With a STRONG immune system, you could have heart disease or you could NOT have heart disease
-- With a WEAK immune system, you could have heart disease or you could NOT have heart disease

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11 Dec 2022, 16:16

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jabhatta2

Quote:

The cause of their deaths, however, was more often heart disease, against which the immune system does not protect, than cancer or infections, which are attacked by the immune system.

I highlighted the word attacked in the quote above, jabhatta2. That word implies the correlation STRONGER IMMUNE SYSTEM ~ LESS LIKELY TO DIE OF CANCER/INFECTIONS

jabhatta2

Same question on the red

When you read the red - Do you comprehend that as saying

-- There is NO relationship/correlation between heart disease vs immune systems.

OR

-- With a STRONG immune system, you could have heart disease or you could NOT have heart disease
-- With a WEAK immune system, you could have heart disease or you could NOT have heart disease

I don't see any difference between the two options that you laid out here, jabhatta2.

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24 Feb 2023, 22:19

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dear AVI avigutman
would you please clarify what two groups are compared? I am total confused after this thread.

I am not sure whether,
among those with weakest immune system, the death from heard disease are more than that from infections/cancers.
or
among the whole study, those with weakest immune system are twice likely to die than those with stronger immune system?
or
among the whole study, those with weakest immune system are more often dead from heart diseases than those with stronger immune system dead from infections/ cancers.

eager to need your help.

thanks in advance.

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25 Feb 2023, 15:04

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zoezhuyan

Here's a bell curve representing the strength of the immune system of all the 85-year-olds in the study.
The people in the dark red region (see image) are twice as likely to die in the next two years as are the people in the other regions.
What are they dying of? Well, that's a separate question! I think you're trying to mix two separate comparisons and that's causing you confusion, zoezhuyan.

Quote:

The cause of their deaths, however, was more often heart disease, against which the immune system does not protect, than cancer or infections, which are attacked by the immune system.

The cause of whose death? 'their' refers to the people in the dark red region.
What are they dying of? Well, they're dying of different things - they didn't all die of the same cause.
If you can imagine a spreadsheet that has a cause-of-death next to each of the people (from the red region) who died in the 2 year-period, well it turns out that a greater number of deaths were caused by heart disease than were caused by cancer or infections.

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Bell curve.jpeg [ 26.05 KiB | Viewed 1842 times ]

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KarishmaB

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GMAT® Official Guide Verbal Review 2019

Practice Question
Question No.:
Online test bank question number : CR01101

A two-year study beginning in 1977 found that, among 85-year-old people, those whose immune systems were weakest were twice as likely to die within two years as others in the study. The cause of their deaths, however, was more often heart disease, against which the immune system does not protect, than cancer or infections, which are attacked by the immune system.

Which of the following, if true, would offer the best prospects for explaining deaths in which weakness of the immune system, though present, played no causal role?

(A) There were twice as many infections among those in the study with the weakest immune systems as among those with the strongest immune systems.

(B) The majority of those in the study with the strongest immune systems died from infection or cancer by 1987.

(C) Some of the drugs that had been used to treat the symptoms of heart disease had a side effect of weakening the immune system.

(D) Most of those in the study who survived beyond the two-year period had recovered from a serious infection sometime prior to 1978.

(E) Those in the study who survived into the 1980s had, in 1976, strengthened their immune systems through drug therapy.

This is a paradox question and you have to explain the paradox.

- Those whose immune systems were weakest were twice as likely to die within two years as others in the study.
- But cause of their deaths was more often heart disease - something which has nothing to do with immune system

This is odd, right? If people with weak systems were the first to go, they should have gone due to some immune system related complication. But this is not so. They often died due to heart disease.

Let's look for an option that w ill explain this:

(A) There were twice as many infections among those in the study with the weakest immune systems as among those with the strongest immune systems.
If people with weak immune systems had many more infections (which makes sense), then it also makes sense that they will die due to those infections and not heart diseases. Hence, we do not get an explanation of the paradox.

(B) The majority of those in the study with the strongest immune systems died from infection or cancer by 1987.
How those with strongest immune systems died is out of scope.

(C) Some of the drugs that had been used to treat the symptoms of heart disease had a side effect of weakening the immune system.
This explains our paradox. If medicine for symptoms of heart disease causes weak immune system, it means that people with heart disease would have weak immune systems too. Perhaps those were the people that we identified with weak immune systems. They died due to heart disease is then understandable since they had heart disease (the medicine is symptomatic treatment only).

(D) Most of those in the study who survived beyond the two-year period had recovered from a serious infection sometime prior to 1978.
Out of scope. We are not worried about people who died after the two year period. We are worried about the cause of death of those who died within the two year period.

(E) Those in the study who survived into the 1980s had, in 1976, strengthened their immune systems through drug therapy.
Again, out of scope. Same reason as that of (D).

Answer (C)

I have a doubt regarding how the question is asked. The question says " would offer the best prospects for explaining deaths in which weakness of the immune system, though present, played no causal role ", especially the "played no casual role" part doesn't it mean that the question asks us to justify or prove that the weak immune system has had a major role in the death of those who died by heart attack? Because when reading the question I interpreted it as give a reason to justify that the cause of those deaths was the weak immune system and not the heart attack itself.

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03 Jan 2024, 14:17

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Danish234

Sorry that we're late to the party here!

For something to "play NO causal role" means that this thing did NOT cause death. This is actually the opposite of what you've described.

From the passage, we get a surprising situation: people with weakened immune systems are dying from heart disease. The reason why this is surprising is that the immune system doesn't fight against heart disease. So, we know that the weakened immune system is NOT causing these deaths.

So why are these people with weakened immune systems dying of heart disease? (C) gives us a timeline to explain this situation: first, people got heart disease. Then, they started taking drugs to treat the heart disease. Then, the drugs weakened their immune system. Finally, the people died of their underlying heart disease. The weakened immune system had nothing to do with their deaths -- it was just a side effect of the drugs.

(C) is the correct answer because it explains how the weakened immune system did NOT cause the deaths.

I hope that helps!

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27 Jul 2024, 03:48

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After tackeling this problem, phraps, I can add some insights:
I believe that illustrating and understanding the story here is an important part of solving this problem.

The story, as I see it:
A total of 100 people are tested, all of whom are 85 years old.
30 people died during these two years.
we are given that:
27 people died from heart disease (HD), and 3 from other causes.
In evaluating these 27 HD individuals (27=3x), we are given that:
2x (18) had a weak immune system, while x (9) had a stronger immune system.
We can observe a correlation relationship (that is the first instinct "The paradox" one can expect):
Low immune system: More deaths. (Is this a coincidence, or did something else cause them to die?)
However, the argument stated that there is no link between immune system and heart disease.

Now, AC C claims that from the beginning, all 27 people with heart disease took medication, which caused some of them to have a weakened immune system.
Then we return to the first conclusion: 2x (18) died from a weakened immune system, whereas x (9) had a stronger immune system.
Pharps, it was the opposite; the 18 deaths among people with a low immune system were caused by heart disease, which is why we saw this 2x correlation.
This is what AC C says, and it resolves our "paradox".

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02 Jun 2025, 07:23

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In the question, aren't they asking what could be the give a reason to explain why weakness of immune system is not relevant? So, if C is the answer, we are saying immune system has a causal role, right?

Which of the following, if true, would offer the best prospects for explaining deaths in which
weakness of the immune system, though present, played no causal role?

KarishmaB

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